From da8c0ab092709e0b1b5646d1bdf5e3adcfd4a155 Mon Sep 17 00:00:00 2001
From: Yichen Jiang <jyc132780208@sina.com>
Date: Wed, 22 Jul 2026 17:34:31 +0800
Subject: [PATCH] fix(session-reference): bind snapshots to prompts

---
 ...6-07-21-cross-session-references.i18n.yaml |  4 +-
 .../2026-07-21-cross-session-references.md    | 14 +--
 .../2026-07-21-cross-session-references.zh.md | 14 +--
 docs/architecture.i18n.yaml                   |  4 +-
 docs/architecture.md                          |  4 +-
 docs/architecture.zh.md                       |  4 +-
 docs/config-catalog.md                        |  6 +-
 docs/cordis-catalog/events.md                 | 40 ++++----
 docs/cordis-catalog/services.md               |  4 +-
 docs/core-data-structures/core.md             | 21 +++--
 docs/core-data-structures/session.md          | 22 ++++-
 docs/event-producer-consumer.md               | 40 ++++----
 docs/module-graph.md                          |  3 +-
 docs/persistence-catalog.md                   | 40 ++++----
 .../goal-session/stdout.expected.jsonl        |  2 +-
 .../advanced-toolchain/stdout.expected.jsonl  |  2 +-
 .../bash-spill/stdout.expected.jsonl          |  2 +-
 .../both-mode-turn/stdout.expected.jsonl      |  2 +-
 .../cancel-tool-calls/stdout.expected.jsonl   |  2 +-
 .../snapshots/cancel/stdout.expected.jsonl    |  2 +-
 .../code-mode-turn/stdout.expected.jsonl      |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../config-options/stdout.expected.jsonl      |  2 +-
 .../cordis-inspect-jsdoc/session.jsonl        |  2 +-
 .../stdout.expected.jsonl                     |  4 +-
 .../error-finish/stdout.expected.jsonl        |  2 +-
 .../escalation-approved/stdout.expected.jsonl |  2 +-
 .../escalation-rejected/stdout.expected.jsonl |  2 +-
 .../snapshots/fs-edit/stdout.expected.jsonl   |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../fs-policy-reject/stdout.expected.jsonl    |  2 +-
 .../fs-read-window/stdout.expected.jsonl      |  2 +-
 .../snapshots/fs-read/stdout.expected.jsonl   |  2 +-
 .../fs-terminal-card/stdout.expected.jsonl    |  2 +-
 .../fs-write-overwrite/stdout.expected.jsonl  |  2 +-
 .../snapshots/fs-write/stdout.expected.jsonl  |  2 +-
 .../goal-command-status/stdout.expected.jsonl |  2 +-
 .../snapshots/handshake/stdout.expected.jsonl |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../hook-cc-pretool-ask/stdout.expected.jsonl |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../lsp-definition/stdout.expected.jsonl      |  2 +-
 .../model-switching/stdout.expected.jsonl     |  2 +-
 .../multi-turn/stdout.expected.jsonl          |  2 +-
 .../parallel-tool-calls/stdout.expected.jsonl |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../reject-extra-dirs/stdout.expected.jsonl   |  2 +-
 .../repeat-tool-guard/stdout.expected.jsonl   |  2 +-
 .../skill-load/stdout.expected.jsonl          |  2 +-
 .../stdout.expected.jsonl                     |  2 +-
 .../subagent-fork/stdout.expected.jsonl       |  2 +-
 .../subagent-mixed/stdout.expected.jsonl      |  2 +-
 .../subagent-multi/stdout.expected.jsonl      |  2 +-
 .../subagent-spawn/stdout.expected.jsonl      |  2 +-
 .../snapshots/text-turn/stdout.expected.jsonl |  2 +-
 .../snapshots/todo-plan/stdout.expected.jsonl |  2 +-
 .../tool-call-turn/stdout.expected.jsonl      |  2 +-
 .../workflow-run/stdout.expected.jsonl        |  2 +-
 .../workspace-context/stdout.expected.jsonl   |  2 +-
 .../workspace-edit/stdout.expected.jsonl      |  2 +-
 packages/context/session-reference/README.md  | 10 +-
 .../context/session-reference/src/index.ts    |  1 +
 .../session-reference/src/projection.ts       |  5 +-
 .../tests/session-reference.spec.ts           | 53 +++++++++--
 .../cordis/tool-cordis/src/api-catalog.ts     | 20 +++-
 packages/core/agent-loop/README.md            |  2 +-
 packages/core/agent-loop/src/loop.ts          | 63 +++++++++++--
 .../tests/contract-regressions.spec.ts        | 61 ++++++++++--
 .../agent-loop/tests/interception.spec.ts     | 49 ++++++++++
 packages/core/agent/README.md                 |  6 +-
 packages/core/agent/src/types.ts              | 19 ++--
 packages/core/session/README.md               |  4 +-
 packages/core/session/src/index.ts            | 21 ++++-
 packages/core/session/src/types.ts            | 35 ++++++-
 packages/core/session/tests/session.spec.ts   | 30 ++++++
 .../examples/acp-demo/tests/built-bin.e2e.ts  | 28 +++++-
 .../session-title/session-title/src/index.ts  |  6 +-
 .../session-title/tests/session-title.spec.ts | 27 ++++++
 packages/ui/acp/README.md                     |  9 +-
 packages/ui/acp/acp-feature-support.md        | 14 +--
 packages/ui/acp/package.json                  |  1 +
 packages/ui/acp/src/index.ts                  | 52 ++++++++++-
 packages/ui/acp/tests/bridge.spec.ts          | 19 ++--
 packages/ui/acp/tests/harness.ts              |  2 +-
 packages/ui/acp/tests/session-list.spec.ts    | 92 +++++++++++++++++++
 packages/ui/acp/tests/stream-update.spec.ts   | 18 ++++
 packages/ui/acp/tsconfig.json                 |  3 +
 packages/ui/tui/src/index.ts                  | 21 ++++-
 .../tui/tests/session-reference.snapshot.ts   | 28 ++++--
 .../snapshots/session-reference.expected.txt  |  2 +-
 packages/ui/tui/tests/tui.spec.ts             | 50 ++++++++++
 scripts/type-equiv.manifest.json              |  1 +
 102 files changed, 838 insertions(+), 248 deletions(-)
 create mode 100644 packages/ui/acp/tests/session-list.spec.ts

diff --git a/.agents/notes/implemented/feature/2026-07-21-cross-session-references.i18n.yaml b/.agents/notes/implemented/feature/2026-07-21-cross-session-references.i18n.yaml
index 33b770c103..9c0118a72d 100644
--- a/.agents/notes/implemented/feature/2026-07-21-cross-session-references.i18n.yaml
+++ b/.agents/notes/implemented/feature/2026-07-21-cross-session-references.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write
-2026-07-21-cross-session-references.md: b8ecae9f1f453ea377de1a59c96e388bdb6f859b
-2026-07-21-cross-session-references.zh.md: 61d294f53c4355cb2d0c0eb616f5eeb46542a1fe
+2026-07-21-cross-session-references.md: bfa015b24cda6c8651829b6a7f0800326da5b502
+2026-07-21-cross-session-references.zh.md: e8e99124f7e2ccfe9fbe97323c17143372017562
diff --git a/.agents/notes/implemented/feature/2026-07-21-cross-session-references.md b/.agents/notes/implemented/feature/2026-07-21-cross-session-references.md
index b8ecae9f1f..bfa015b24c 100644
--- a/.agents/notes/implemented/feature/2026-07-21-cross-session-references.md
+++ b/.agents/notes/implemented/feature/2026-07-21-cross-session-references.md
@@ -20,21 +20,21 @@ The service uses `ctx.sessionQuery.readSurface(sessionId)`, which loads one live
 
 Preparation deduplicates in first-appearance order, rejects the target id, enforces a configurable limit with a hard maximum of three references, and performs all reads in parallel. It returns no partially prepared context: any read, cancellation, validation, or budget error rejects the operation before `send()` or `steer()`. Cancellation races in-flight discovery and exact reads, so a host settles promptly even when a persistence backend cannot interrupt its pending operation; any late backend settlement is observed but cannot enqueue the message. A source is read before enqueue, so later source messages, compaction, deletion, or persistence replacement cannot change the target session.
 
-Projection retains direct-user messages and steering, completed assistant text, and checkpoint user messages carrying the canonical source exported by `dsh-compact`. That marker is part of the compaction capability contract rather than a backend package name. Projection excludes shadowed pre-compaction nodes, tools and results, reasoning, injected context, other plugin user messages, log-only records, and incomplete assistant chunks. Repeated compaction therefore exposes only the latest folded checkpoint lineage still on the current surface plus its retained tail; there is no raw/current switch and no shadow recovery.
+Projection retains direct-user messages and steering, completed assistant text, and checkpoint user messages carrying the canonical source exported by `dsh-compact`. That marker is part of the compaction capability contract rather than a backend package name. When a source prompt already contains baked prefix context, projection reads only its model-hidden display content, so referencing that target later does not recursively propagate an earlier snapshot. Projection excludes shadowed pre-compaction nodes, tools and results, reasoning, injected context, other plugin user messages, log-only records, and incomplete assistant chunks. Repeated compaction therefore exposes only the latest folded checkpoint lineage still on the current surface plus its retained tail; there is no raw/current switch and no shadow recovery.
 
-One aggregated context is serialized as JSON beneath a fixed untrusted-background warning. The warning tells the model not to follow instructions, permission claims, or tool requests from referenced sessions unless the current user repeats them. Tag-safe serialization emits every data `<` as the lossless JSON escape `\u003c`; source strings therefore cannot spell the surrounding XML-like tags. The same serializer drives each source's independent byte accounting. Context metadata records source and retention facts, while the visible bytes persist through the existing `context/message` event so target replay satisfies the model-visible/log-reconstructable invariant without a new event type.
+One aggregated context is serialized as JSON beneath a fixed untrusted-background warning. The warning tells the model not to follow instructions, permission claims, or tool requests from referenced sessions unless the current user repeats them. Tag-safe serialization emits every data `<` as the lossless JSON escape `\u003c`; source strings therefore cannot spell the surrounding XML-like tags. The `## My request:` text is a routing cue rather than the trust boundary: referenced data may spell those words inside a JSON string, but it cannot forge the closing `</referenced-sessions>` tag or escape the data region. The same serializer drives each source's independent byte accounting. The context declares `prompt-prefix` placement, so AgentLoop persists one `user/message` or `steering/message` containing the snapshot, `## My request:` delimiter, and effective direct prompt. Its model-hidden envelope retains the direct display content and source/retention metadata. Target replay therefore satisfies the model-visible/log-reconstructable invariant without a new event type or a separate user-role context message.
 
 ## Message ownership
 
-`send()` and `steer()` snapshot content, resolved source, and contexts together as one deeply frozen lossless-JSON inbox record. Synthetic `inject()` accepts source and model-hidden metadata but not attached contexts, which belong to inbox messages. A claimed ordinary message exposes its attached contexts as the default `agent/prompt-submit` additional contexts; a block writes neither user message nor contexts. The waterfall's returned allow is authoritative, so a listener wrapping `next()` preserves downstream content and contexts unless it intentionally replaces them. Drained steering bypasses `agent/prompt-submit` and writes `steering/message` before its contexts. Late steering retains the same record when converted to queued input, while cancellation, disposal, and terminal discard drop message and contexts together. `agent/queued` reports the frozen contexts so the observation event describes the complete retained item.
+`send()` and `steer()` snapshot content, resolved source, and contexts together as one deeply frozen lossless-JSON inbox record. Synthetic `inject()` accepts source and model-hidden metadata but not attached contexts, which belong to inbox messages. A claimed ordinary message exposes its attached contexts as the default `agent/prompt-submit` additional contexts; a block writes neither user message nor contexts. The waterfall's returned allow is authoritative, so a listener wrapping `next()` preserves downstream content and contexts unless it intentionally replaces them. After admission, absent or `separate` placement writes an independent `context/message`, while `prompt-prefix` placement bakes context and the effective request into one prompt event. Drained steering bypasses `agent/prompt-submit` but applies the same placement split. Late steering retains the same record when converted to queued input, while cancellation, disposal, and terminal discard drop message and contexts together. `agent/queued` reports the frozen contexts so the observation event describes the complete retained item.
 
 This preserves host driving semantics: TUI decides `send()` versus `steer()` from the agent state after preparation, so only its queued path dispatches UserPromptSubmit hooks; ACP continues to call `send()` once per `session/prompt`. Reference preparation is not a new steering protocol and does not create a turn by itself.
 
 ## Host adapters
 
-TUI combines session candidates with the existing `@` file provider. Candidate lookup follows the editor's cancellation signal, and session id, cwd, and mention labels escape external terminal controls while the canonical URI retains the original id. TUI prepares only submissions containing structured mentions, disables duplicate submit while awaiting snapshots, restores failed input, and renders persisted session-reference context as a compact source list instead of exposing the complete JSON in the terminal.
+TUI combines session candidates with the existing `@` file provider. Each candidate displays the latest folded session title and falls back to the session id; lookup follows the editor's cancellation signal, and session id, cwd, and mention labels escape external terminal controls while the canonical URI retains the original id. TUI prepares only submissions containing structured mentions, disables duplicate submit while awaiting snapshots, restores failed input, renders the prompt envelope's display content as the user message, and renders its session-reference metadata as a compact source list instead of exposing the complete JSON in the terminal.
 
-ACP detects direct slash commands from ordinary prompt flattening before extracting `dsh-session:` resource links and canonical inline mentions, so URI-shaped command arguments remain opaque while ordinary resource-link rendering is preserved. A valid reference without the optional service returns a capability-unavailable RPC error, and preparation failure occurs before the in-flight turn slot and agent send. A preparation-specific abort owner makes `session/cancel` and bridge teardown stop pending reads. Picker UI remains an ACP client responsibility.
+ACP detects direct slash commands from ordinary prompt flattening before extracting `dsh-session:` resource links and canonical inline mentions, so URI-shaped command arguments remain opaque while ordinary resource-link rendering is preserved. Standard `session/list` exposes each loadable session's folded title and, when references are mounted, a canonical URI under `_meta["deepseek-harness/sessionReference"]`; a client can use `title ?? sessionId` as the resource-link name. A valid reference without the optional service returns a capability-unavailable RPC error, and preparation failure occurs before the in-flight turn slot and agent send. A preparation-specific abort owner makes `session/cancel` and bridge teardown stop pending reads. Picker UI remains an ACP client responsibility because ACP does not define a cross-session mention menu.
 
 ## Budget and retention
 
@@ -45,13 +45,15 @@ Each of at most three references is independently capped at 65,536 UTF-8 bytes b
 - **Wait for SQLite FTS5** — rejected because snapshot correctness requires exact id reads and canonical surface folding, not content search. FTS improves discovery only.
 - **Put mention syntax in `Agent.send()`** — rejected because it would make the core protocol parse TUI/ACP presentation and prevent typed non-text hosts from sharing the semantic layer.
 - **Implement references inside TUI and ACP separately** — rejected because projection, security warning, retention, and persistence would drift across hosts.
+- **Place a separate user-role context message beside the prompt** — rejected because two adjacent user messages weaken the prompt's deictic binding: in `@foo what does this session discuss?`, the model may resolve “this session” as the current conversation instead of the referenced snapshot.
+- **Bake the prefix host-side before `send()`** — rejected because `agent/prompt-submit` must inspect and rewrite only the direct prompt. The effective prompt and attached contexts meet only after admission in AgentLoop, which can apply an `allow.content` rewrite consistently to both combined model content and `envelope.displayContent`; earlier host assembly would expose snapshot bytes to the hook or let those two views diverge.
 - **Replay the raw source log or restore shadowed events** — rejected because compact defines the current model surface and may intentionally retire sensitive or expensive history.
 - **Resume or fork the source** — rejected because the feature supplies read-only background for one target message, not identity or lifecycle continuity.
 - **Inject at request time by rereading the source** — rejected because the reference would become nondeterministic, cancellation races could alter its bytes, and target replay would depend on external mutable state.
 
 ## Verification
 
-Unit and integration coverage pins URI round-trips and text-boundary punctuation, explicit malformed references, candidate ranking, terminal-control escaping, projection exclusions, backend-independent compact checkpoints, tag-safe framing, deduplication, self-reference, count limits, all-or-nothing reads, prompt cancellation against a non-settling storage read, independent per-source byte retention, frozen message ownership, prompt blocking, send/steer ordering, missing capability, ordinary ACP resource links, opaque ACP command arguments, and compact TUI rendering. A keyless TUI snapshot runs the real agent loop: the source surface replaces old user/assistant history with a compact checkpoint, the target submits a mention, and the captured model request contains the checkpoint and retained tail but not either shadowed string.
+Unit and integration coverage pins URI round-trips and text-boundary punctuation, explicit malformed references, title-aware candidate ranking, terminal-control escaping, projection exclusions, non-recursive prompt-envelope projection, backend-independent compact checkpoints, tag-safe framing, deduplication, self-reference, count limits, all-or-nothing reads, prompt cancellation against a non-settling storage read, independent per-source byte retention, frozen message ownership, prompt blocking, send/steer placement, title isolation, missing capability, title-aware ACP session listing, ordinary ACP resource links, opaque ACP command arguments, and compact TUI/ACP replay. A keyless TUI snapshot runs the real agent loop: the source surface replaces old user/assistant history with a compact checkpoint, the target submits a mention, and the captured model request contains one user message ordered as snapshot, request delimiter, and current prompt, without either shadowed string.
 
 ## Consequences
 
diff --git a/.agents/notes/implemented/feature/2026-07-21-cross-session-references.zh.md b/.agents/notes/implemented/feature/2026-07-21-cross-session-references.zh.md
index 61d294f53c..e8e99124f7 100644
--- a/.agents/notes/implemented/feature/2026-07-21-cross-session-references.zh.md
+++ b/.agents/notes/implemented/feature/2026-07-21-cross-session-references.zh.md
@@ -20,21 +20,21 @@ TUI 与 ACP（Agent Client Protocol）用户需要把另一场对话中的相关
 
 准备过程按首次出现的顺序去重、拒绝目标会话自身的 id，并且执行可配置的数量限制，但引用硬上限为三个，所有读取均并行执行。该过程不会返回部分完成的上下文：任何读取、取消、校验或预算错误都会在调用 `send()` 或 `steer()` 前拒绝本次操作。取消会与进行中的候选发现和精确读取竞速，因此即使持久化后端无法中断待处理操作，宿主也能及时结束等待；后端迟到的完成结果仍会被观察，但不能让消息入队。源会话在入队前完成读取，因此源会话后续新增消息、执行压缩、被删除或替换持久化内容，都无法改变目标会话中的快照。
 
-投影会保留直接用户消息与 steering（中途引导）、已完成的 assistant 文本，以及携带由 `dsh-compact` 导出的规范来源标记的检查点用户消息。该标记属于压缩功能契约的一部分，而非某个后端包名称。投影会排除压缩前已被遮蔽的节点、工具及其结果、推理（reasoning）、注入的上下文、其他插件用户消息、仅用于日志的记录，以及尚未完成的 assistant 分片。因此，重复压缩只会暴露当前表层仍保留的最新折叠检查点谱系及其尾部消息；系统不提供 raw/current 开关，也不恢复被遮蔽的内容。
+投影会保留直接用户消息与 steering（中途引导）、已完成的 assistant 文本，以及携带由 `dsh-compact` 导出的规范来源标记的检查点用户消息。该标记属于压缩功能契约的一部分，而非某个后端包名称。当源提示词已包含合并写入的前缀上下文时，投影只读取其模型不可见的显示内容，因此后续引用该目标不会递归传播先前的快照。投影会排除压缩前已被遮蔽的节点、工具及其结果、推理（reasoning）、注入的上下文、其他插件用户消息、仅用于日志的记录，以及尚未完成的 assistant 分片。因此，重复压缩只会暴露当前表层仍保留的最新折叠检查点谱系及其尾部消息；系统不提供 raw/current 开关，也不恢复被遮蔽的内容。
 
-系统把一个聚合上下文序列化为 JSON，并置于固定的不可信背景警告之后。该警告要求模型不要遵循被引用会话中的指令、权限声明或工具请求，除非当前用户再次提出这些内容。标签安全序列化会把数据中的每个 `<` 无损转义为 JSON `\u003c`；因此源字符串无法拼出外围类似 XML 的标签。同一个序列化器会独立核算每个源的字节数。上下文元数据记录来源与保留事实；模型可见字节通过现有 `context/message` 事件持久化，使目标回放在不新增事件类型的前提下满足「模型可见／日志可重建」不变量。
+系统把一个聚合上下文序列化为 JSON，并置于固定的不可信背景警告之后。该警告要求模型不要遵循被引用会话中的指令、权限声明或工具请求，除非当前用户再次提出这些内容。标签安全序列化会把数据中的每个 `<` 无损转义为 JSON `\u003c`；因此源字符串无法拼出外围类似 XML 的标签。`## My request:` 文本只是路由提示，不是信任边界：被引用数据可以在 JSON 字符串中包含这些词，但无法伪造闭合的 `</referenced-sessions>` 标签，也无法逃逸数据区域。同一个序列化器会独立核算每个源的字节数。该上下文声明 `prompt-prefix` 放置方式，因此 AgentLoop 会持久化一条 `user/message` 或 `steering/message`，其中包含快照、`## My request:` 分隔符和最终生效的直接提示词。其模型不可见封套保留直接显示内容以及来源与保留元数据。因此，目标回放无需新增事件类型或单独的用户角色上下文消息，也能满足「模型可见／日志可重建」不变量。
 
 ## 消息所有权
 
-`send()` 与 `steer()` 会把内容、解析后的来源和上下文一起快照为一条深度冻结、无损 JSON 的收件箱记录。合成的 `inject()` 接受来源和模型不可见的元数据，但不接受附加上下文，因为上下文属于收件箱消息。普通消息被认领后，其附带的上下文会作为 `agent/prompt-submit` 的默认附加上下文公开；提示词被阻止时，系统既不写入用户消息，也不写入上下文。waterfall（瀑布式事件）返回的 allow 结果具有最终权威性，因此监听器包装 `next()` 时会保留下游内容与上下文，除非它有意替换这些值。排空 steering 消息时会绕过 `agent/prompt-submit`，先写入 `steering/message`，再写入其上下文。延迟到达的 steering 转换为排队输入时保留同一条记录；取消、dispose（资源释放）和到达终止态后的丢弃则会同时丢弃消息与上下文。`agent/queued` 会报告已冻结的上下文，使观察事件能够描述完整的保留项。
+`send()` 与 `steer()` 会把内容、解析后的来源和上下文一起快照为一条深度冻结、无损 JSON 的收件箱记录。合成的 `inject()` 接受来源和模型不可见的元数据，但不接受附加上下文，因为上下文属于收件箱消息。普通消息被认领后，其附带的上下文会作为 `agent/prompt-submit` 的默认附加上下文公开；提示词被阻止时，系统既不写入用户消息，也不写入上下文。waterfall（瀑布式事件）返回的 allow 结果具有最终权威性，因此监听器包装 `next()` 时会保留下游内容与上下文，除非它有意替换这些值。消息被接纳后，未指定放置方式或指定为 `separate` 时会写入独立的 `context/message`；指定为 `prompt-prefix` 时则会把上下文与最终生效的请求合并写入同一个提示词事件。排空 steering 消息时会绕过 `agent/prompt-submit`，但采用相同的放置方式分流。延迟到达的 steering 转换为排队输入时保留同一条记录；取消、dispose（资源释放）和到达终止态后的丢弃则会同时丢弃消息与上下文。`agent/queued` 会报告已冻结的上下文，使观察事件能够描述完整的保留项。
 
 这保留了宿主的驱动语义：TUI 在准备完成后根据 agent 状态决定调用 `send()` 还是 `steer()`，因此只有它的排队路径才会分派 UserPromptSubmit 钩子；ACP 则继续调用 `send()`，每个 `session/prompt` 调用一次。引用准备过程不是新的 steering 协议，本身也不会创建轮次。
 
 ## 宿主适配器
 
-TUI 把会话候选与现有 `@` 文件提供方组合在一起。候选查询遵循编辑器的取消信号；session id、cwd 和提及标签中的外部终端控制字符会被转义，但规范 URI 仍保留原始 id。TUI 只准备包含结构化提及标记的提交；等待快照时禁用重复提交；失败时恢复输入；渲染持久化的会话引用上下文时只显示精简的来源列表，不在终端中暴露完整 JSON。
+TUI 把会话候选与现有 `@` 文件提供方组合在一起。每个候选项显示最新折叠后的会话标题，没有标题时回退到 session id。候选查询遵循编辑器的取消信号；session id、cwd 和提及标签中的外部终端控制字符会被转义，但规范 URI 仍保留原始 id。TUI 只准备包含结构化提及标记的提交；等待快照时禁用重复提交；失败时恢复输入；它把提示词封套的显示内容渲染为用户消息，并把其中的会话引用元数据渲染为精简的来源列表，不在终端中暴露完整 JSON。
 
-ACP 先从普通提示词扁平化结果中检测直接斜杠命令，再提取 `dsh-session:` 资源链接和规范的行内提及标记，因此形如 URI 的命令参数保持不透明，同时保留普通资源链接的渲染方式。若引用有效但可选服务未挂载，系统会返回「功能不可用」RPC 错误；准备失败会发生在占用进行中轮次槽位并调用 agent send 之前。引用准备过程单独拥有中止控制权，因此 `session/cancel` 和桥接释放都能停止待处理的读取。选择器 UI 仍由 ACP 客户端负责。
+ACP 先从普通提示词扁平化结果中检测直接斜杠命令，再提取 `dsh-session:` 资源链接和规范的行内提及标记，因此形如 URI 的命令参数保持不透明，同时保留普通资源链接的渲染方式。标准 `session/list` 会公开每个可加载会话折叠后的标题；挂载会话引用功能时，还会在 `_meta["deepseek-harness/sessionReference"]` 下公开规范 URI。客户端可以使用 `title ?? sessionId` 作为资源链接名称。若引用有效但可选服务未挂载，系统会返回「功能不可用」RPC 错误；准备失败会发生在占用进行中轮次槽位并调用 agent send 之前。引用准备过程单独拥有中止控制权，因此 `session/cancel` 和桥接释放都能停止待处理的读取。选择器 UI 仍由 ACP 客户端负责，因为 ACP 未定义跨会话提及菜单。
 
 ## 预算与保留策略
 
@@ -45,13 +45,15 @@ ACP 先从普通提示词扁平化结果中检测直接斜杠命令，再提取
 - **等待 SQLite FTS5**：不予采纳，因为快照正确性依赖按准确 id 读取和规范表层折叠，而不是内容搜索。FTS 只改进候选发现。
 - **把提及标记语法放入 `Agent.send()`**：不予采纳，因为这会迫使核心协议解析 TUI／ACP 的表现层，并阻止带类型的非文本宿主复用同一语义层。
 - **在 TUI 和 ACP 中分别实现引用**：不予采纳，因为投影、安全警告、保留策略和持久化会在不同宿主之间逐渐偏离。
+- **在提示词旁放置单独的用户角色上下文消息**：不予采纳，因为相邻的两条用户消息会削弱提示词的指示语绑定：在 `@foo what does this session discuss?` 中，模型可能把「this session」解析为当前对话，而不是被引用的快照。
+- **在调用 `send()` 前由宿主合并前缀**：不予采纳，因为 `agent/prompt-submit` 必须只检查和改写直接提示词。最终生效的提示词与附加上下文只有在 AgentLoop 接纳后才汇合；此时 AgentLoop 可以把 `allow.content` 改写一致应用于合并后的模型内容和 `envelope.displayContent`。若由宿主更早组装，就会向该钩子暴露快照字节，或使这两个视图发生偏离。
 - **回放原始源日志或恢复被遮蔽的事件**：不予采纳，因为压缩定义了当前模型表层，并且可能有意淘汰敏感或开销高昂的历史内容。
 - **恢复或 fork 源会话**：不予采纳，因为本功能只为一条目标消息提供只读背景，不提供身份或生命周期连续性。
 - **在请求时重新读取源会话并注入**：不予采纳，因为这会让引用变得不确定，取消竞态可能改变其字节内容，目标回放也会依赖可变的外部状态。
 
 ## 验证
 
-单元与集成测试覆盖 URI 无损往返与文本边界标点、显式格式错误的引用、候选排序、终端控制字符转义、投影排除规则、与后端无关的压缩检查点、标签安全封套、去重、自引用、数量限制、读取的全有或全无、存储读取不结束时取消提示词、逐源独立字节保留、冻结的消息所有权、提示词阻止、send／steer 顺序、功能缺失、普通 ACP 资源链接、不透明的 ACP 命令参数，以及 TUI 精简渲染。无密钥 TUI 快照会运行真实的 agent loop（智能体循环）：源表层用一个压缩检查点替换旧的用户／assistant 历史，目标会话提交一个提及标记，捕获到的模型请求包含该检查点和保留的尾部消息，但不包含任一被遮蔽的字符串。
+单元与集成测试覆盖 URI 无损往返与文本边界标点、显式格式错误的引用、会考虑标题的候选排序、终端控制字符转义、投影排除规则、提示词封套的非递归投影、与后端无关的压缩检查点、标签安全封套、去重、自引用、数量限制、读取的全有或全无、存储读取不结束时取消提示词、逐源独立字节保留、冻结的消息所有权、提示词阻止、send／steer 放置方式、标题隔离、功能缺失、包含标题信息的 ACP 会话列表、普通 ACP 资源链接、不透明的 ACP 命令参数，以及精简的 TUI／ACP 回放。无密钥 TUI 快照会运行真实的 agent loop（智能体循环）：源表层用一个压缩检查点替换旧的用户／assistant 历史，目标会话提交一个提及标记，捕获到的模型请求只包含一条用户消息，其中依次为快照、请求分隔符和当前提示词，并且不包含任一被遮蔽的字符串。
 
 ## 后果
 
diff --git a/docs/architecture.i18n.yaml b/docs/architecture.i18n.yaml
index 13c7764547..f6995ddf5a 100644
--- a/docs/architecture.i18n.yaml
+++ b/docs/architecture.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write
-architecture.md: beace4d9fe54772fefc7c968352aa42638e1c9e8
-architecture.zh.md: 0629fe90a3e3c608e725f9291c3ebaf63940dc25
+architecture.md: f0075e1b946c4826e6bced8139aa243d1c3bf3b0
+architecture.zh.md: 7215f359837faaa3f886719838175ce39b682517
diff --git a/docs/architecture.md b/docs/architecture.md
index beace4d9fe..f0075e1b94 100644
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -80,10 +80,10 @@ forever:
   TURN:
     'turn/start'
     claimed message + contexts -> agent/prompt-submit
-      allowed prompt -> 'user/message' plus contexts
+      allowed prompt -> 'user/message' with prompt-prefix context baked in; append separate contexts
       blocked prompt -> 'prompt/blocked' -> 'turn/end'(rejected)
     STEP loop:
-      drain each steering message before its contexts (no prompt-submit)
+      drain steering with the same prefix/separate context placement (no prompt-submit)
       assemble system prompt and tool schemas
       agent/session-prefix (first step)
       agent/pre-step
diff --git a/docs/architecture.zh.md b/docs/architecture.zh.md
index 0629fe90a3..7215f35983 100644
--- a/docs/architecture.zh.md
+++ b/docs/architecture.zh.md
@@ -80,10 +80,10 @@ forever:
   TURN:
     'turn/start'
     claimed message + contexts -> agent/prompt-submit
-      allowed prompt -> 'user/message' plus contexts
+      allowed prompt -> 'user/message' with prompt-prefix context baked in; append separate contexts
       blocked prompt -> 'prompt/blocked' -> 'turn/end'(rejected)
     STEP loop:
-      drain each steering message before its contexts (no prompt-submit)
+      drain steering with the same prefix/separate context placement (no prompt-submit)
       assemble system prompt and tool schemas
       agent/session-prefix (first step)
       agent/pre-step
diff --git a/docs/config-catalog.md b/docs/config-catalog.md
index 77884d1c6d..94582ba2cd 100644
--- a/docs/config-catalog.md
+++ b/docs/config-catalog.md
@@ -11,7 +11,7 @@ A `Requires:` line lists the service keys the plugin `inject`s: its `cordis.yml`
 
 ## `@deepseek-ai/dsh-acp`
 
-Requires: `agents` · `commands` · `sessionPersistence` · `tools` · `userInteraction` · `llm` · `systemPrompt`
+Requires: `agents` · `commands` · `sessionPersistence` · `sessionQuery` · `tools` · `userInteraction` · `llm` · `systemPrompt`
 
 ```ts config-catalog
 /** Plugin config: the agent template ACP sessions are created from. */
@@ -27,7 +27,7 @@ export interface AcpConfig {
 
 Depends on: `Stream` (`@agentclientprotocol/sdk`)
 
-Source: [`packages/ui/acp/src/index.ts:256`](../packages/ui/acp/src/index.ts)
+Source: [`packages/ui/acp/src/index.ts:264`](../packages/ui/acp/src/index.ts)
 
 ## `@deepseek-ai/dsh-acp-demo`
 
@@ -983,7 +983,7 @@ export interface Config {
 }
 ```
 
-Source: [`packages/session-title/session-title/src/index.ts:69`](../packages/session-title/session-title/src/index.ts)
+Source: [`packages/session-title/session-title/src/index.ts:70`](../packages/session-title/session-title/src/index.ts)
 
 ## `@deepseek-ai/dsh-session-title-all-messages-llm`
 
diff --git a/docs/cordis-catalog/events.md b/docs/cordis-catalog/events.md
index ffd7561617..f2b26f9a17 100644
--- a/docs/cordis-catalog/events.md
+++ b/docs/cordis-catalog/events.md
@@ -32,7 +32,7 @@ Effective broad cancellation was requested, before queued/steering work is clear
 
 Types: [Agent](../core-data-structures/core.md) · [AgentCancelCause](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:210`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:217`](../../packages/core/agent/src/types.ts)
 
 ### `agent/created` — emit
 
@@ -54,7 +54,7 @@ A fully configured agent and live session were published. Setup is composition-o
 
 Types: [Agent](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:172`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:179`](../../packages/core/agent/src/types.ts)
 
 ### `agent/disposed` — emit
 
@@ -74,7 +74,7 @@ An agent left the registry; AgentLoop emits this after driver quiescence but bef
 
 Types: [Agent](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:181`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:188`](../../packages/core/agent/src/types.ts)
 
 ### `agent/error` — emit
 
@@ -96,7 +96,7 @@ A step or turn errored. The loop reports a failure here (plus the logger) even w
 
 Types: [Agent](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:358`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:365`](../../packages/core/agent/src/types.ts)
 
 ### `agent/post-step` — serial
 
@@ -119,7 +119,7 @@ Awaited serial checkpoint after the response, real or synthetic tool results, in
 
 Types: [Agent](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:308`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:315`](../../packages/core/agent/src/types.ts)
 
 ### `agent/pre-step` — serial
 
@@ -142,7 +142,7 @@ Awaited serial checkpoint before `step/start`; appends land outside the pending
 
 Types: [Agent](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:239`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:246`](../../packages/core/agent/src/types.ts)
 
 ### `agent/prompt-submit` — waterfall
 
@@ -169,7 +169,7 @@ Allow, rewrite, or block one claimed prompt before it becomes a user message. Ca
 
 Types: [Agent](../core-data-structures/core.md) · [ContentBlock](../core-data-structures/core.md) · [MessageSource](../core-data-structures/core.md) · [PromptDecision](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:255`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:262`](../../packages/core/agent/src/types.ts)
 
 ### `agent/queued` — emit
 
@@ -190,7 +190,7 @@ Detached, frozen content entered the agent's inbox. Source defaults have already
 
 Types: [Agent](../core-data-structures/core.md) · [ContentBlock](../core-data-structures/core.md) · [HookContext](../core-data-structures/core.md) · [MessageSource](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:200`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:207`](../../packages/core/agent/src/types.ts)
 
 ### `agent/request` — waterfall
 
@@ -215,7 +215,7 @@ Replace the frozen call configuration. Model-visible content must use logged cha
 
 Types: [Agent](../core-data-structures/core.md) · [LlmCallConfig](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:269`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:276`](../../packages/core/agent/src/types.ts)
 
 ### `agent/request-error` — waterfall
 
@@ -241,7 +241,7 @@ Recover a model-request failure after its failed step has closed. `retry` opens
 
 Types: [Agent](../core-data-structures/core.md) · [LlmFailure](../core-data-structures/llm-streaming.md) · [RequestError](../core-data-structures/core.md) · [RequestErrorDecision](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:323`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:330`](../../packages/core/agent/src/types.ts)
 
 ### `agent/session-prefix` — waterfall
 
@@ -267,7 +267,7 @@ Compose request-only messages placed before derived history. The frozen result i
 
 Types: [Agent](../core-data-structures/core.md) · [Message](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:284`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:291`](../../packages/core/agent/src/types.ts)
 
 ### `agent/session-start` — emit
 
@@ -289,7 +289,7 @@ The session lifecycle began, once before the first turn. Use `agent.inject()` to
 
 Types: [Agent](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md) · [SessionStartSource](../core-data-structures/core.md)
 
-Source: [`packages/core/agent/src/types.ts:223`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:230`](../../packages/core/agent/src/types.ts)
 
 ### `agent/status` — emit
 
@@ -309,7 +309,7 @@ Agent status changed (`idle` ⇄ `running`, or → `disposed`). `send()` does no
 
 Types: [Agent](../core-data-structures/core.md) · [AgentStatus](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:190`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:197`](../../packages/core/agent/src/types.ts)
 
 ### `agent/step-result` — waterfall
 
@@ -332,7 +332,7 @@ Waterfall: post-process the assembled assistant Message before tool dispatch (va
 
 Types: [Agent](../core-data-structures/core.md) · [Message](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:296`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:303`](../../packages/core/agent/src/types.ts)
 
 ### `agent/turn-continuation` — waterfall
 
@@ -354,7 +354,7 @@ Override whether the turn continues. The default continues after tool calls or s
 
 Types: [Agent](../core-data-structures/core.md) · [ContinuationDecision](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:334`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:341`](../../packages/core/agent/src/types.ts)
 
 ### `agent/turn-stop` — serial
 
@@ -376,7 +376,7 @@ Monotonic terminal-stop checkpoint after continuation and steering are folded; a
 
 Types: [Agent](../core-data-structures/core.md) · [ContinuationStop](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
 
-Source: [`packages/core/agent/src/types.ts:345`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:352`](../../packages/core/agent/src/types.ts)
 
 ## `agent-loop/*`
 
@@ -572,7 +572,7 @@ Creation announcement during session publication. A synchronous throw vetoes and
 
 Types: [Scoped](../core-data-structures/scope.md) · [Session](../core-data-structures/session.md)
 
-Source: [`packages/core/session/src/index.ts:68`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:77`](../../packages/core/session/src/index.ts)
 
 ### `session/disposed` — emit
 
@@ -593,7 +593,7 @@ Emitted once when an announced session leaves the store, including publication r
 
 Types: [Scoped](../core-data-structures/scope.md) · [Session](../core-data-structures/session.md)
 
-Source: [`packages/core/session/src/index.ts:78`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:87`](../../packages/core/session/src/index.ts)
 
 ### `session/event` — emit
 
@@ -616,7 +616,7 @@ Post-commit, fire-and-forget append feed. The listener snapshot resolves before
 
 Types: [Scoped](../core-data-structures/scope.md) · [Session](../core-data-structures/session.md) · [SessionEvent](../core-data-structures/core.md)
 
-Source: [`packages/core/session/src/index.ts:90`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:99`](../../packages/core/session/src/index.ts)
 
 ### `session/flush` — parallel
 
@@ -637,7 +637,7 @@ Awaited parallel durability checkpoint: every listener runs and the caller await
 
 Types: [Scoped](../core-data-structures/scope.md) · [Session](../core-data-structures/session.md)
 
-Source: [`packages/core/session/src/index.ts:100`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:109`](../../packages/core/session/src/index.ts)
 
 ## `subagent/*`
 
diff --git a/docs/cordis-catalog/services.md b/docs/cordis-catalog/services.md
index 8774d5dabe..2b34a25d69 100644
--- a/docs/cordis-catalog/services.md
+++ b/docs/cordis-catalog/services.md
@@ -1056,7 +1056,7 @@ fork(source: SessionForkSource, boundary?: number, childSessionId?: SessionId):
 
 Types: [CreateSessionOptions](../core-data-structures/persistence.md) · [OutOfBandSessionEventType](../core-data-structures/session.md) · [Session](../core-data-structures/session.md) · [SessionEvent](../core-data-structures/core.md) · [SessionEventMap](../core-data-structures/session.md) · [SessionId](../core-data-structures/core.md) · [TurnTrigger](../core-data-structures/session.md)
 
-Source: [`packages/core/session/src/index.ts:592`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:603`](../../packages/core/session/src/index.ts)
 
 ## `ctx.sessionTitle` — `SessionTitleService`
 
@@ -1090,7 +1090,7 @@ register(provider: SessionTitleProvider): () => Promise<void>
 
 Types: [Session](../core-data-structures/session.md) · [SessionTitleProvider](../core-data-structures/session-title.md) · [SessionTitleSnapshot](../core-data-structures/session-title.md)
 
-Source: [`packages/session-title/session-title/src/index.ts:282`](../../packages/session-title/session-title/src/index.ts)
+Source: [`packages/session-title/session-title/src/index.ts:284`](../../packages/session-title/session-title/src/index.ts)
 
 ## `ctx.skills` — `SkillService`
 
diff --git a/docs/core-data-structures/core.md b/docs/core-data-structures/core.md
index 0fbc1c108b..c0fc885d9b 100644
--- a/docs/core-data-structures/core.md
+++ b/docs/core-data-structures/core.md
@@ -453,7 +453,7 @@ The process-local initiator carried by `ctx.agents` is the exact `Agent` above,
 
 ## Interception decisions
 
-Each `agent/*` interception waterfall returns a small, seam-specific typed union — the unified Decision idiom (the tool seams' `PreToolDecision`/`PostToolDecision` in [tools.md](tools.md) follow the same shape). A CC/Codex hook bridge maps its `permissionDecision`/`decision`/`continue`/`additionalContext` fields onto these; a native plugin returns them directly. Prompt and post-tool decisions share one model-facing context shape, `HookContext`, which is `inject()`ed as a `context/message` and therefore carries a REQUIRED `source` (a missing source would default to `{kind:'user'}` and mislabel plugin context as a user prompt). Its `content` reaches the model verbatim as a user-role message, while JSON `meta` persists plugin state without exposing it to the model. Both decisions carry `additionalContexts[]` so every entry preserves its own provenance and metadata. Continuation reasons are steering messages instead and deliberately use the narrower content/source shape.
+Each `agent/*` interception waterfall returns a small, seam-specific typed union — the unified Decision idiom (the tool seams' `PreToolDecision`/`PostToolDecision` in [tools.md](tools.md) follow the same shape). A CC/Codex hook bridge maps its `permissionDecision`/`decision`/`continue`/`additionalContext` fields onto these; a native plugin returns them directly. Prompt and post-tool decisions share one model-facing context shape, `HookContext`, which carries a REQUIRED `source` (a missing source would default to `{kind:'user'}` and mislabel plugin context as a user prompt). Its `content` reaches the model verbatim as user-role input, while JSON `meta` persists plugin state without exposing it to the model. Absent or `separate` placement becomes `context/message`; `prompt-prefix` placement is available to prompt and steering inbox attachments and bakes the context before the effective request in the same message. Both decisions carry `additionalContexts[]` so every entry preserves its own provenance, metadata, and placement. Continuation reasons are steering messages instead and deliberately use the narrower content/source shape.
 
 Source: [`packages/core/agent/src/types.ts`](../../packages/core/agent/src/types.ts)
 
@@ -462,6 +462,12 @@ Source: [`packages/core/agent/src/types.ts`](../../packages/core/agent/src/types
 interface HookContext {
   content: ContentBlock[]
   source: MessageSource
+  /**
+   * Model placement. Absent or `separate` records an independent
+   * `context/message`; `prompt-prefix` prepends this context and a stable
+   * request delimiter to the same user-role message as its attached prompt.
+   */
+  placement?: 'separate' | 'prompt-prefix'
   /** Opaque JSON state retained in the session event but hidden from the model. */
   meta?: JsonValue
 }
@@ -471,12 +477,13 @@ interface HookContext {
 
 ```ts type-equiv
 /**
- * Prompt interception result. `allow.content` replaces the prompt and each
- * `additionalContexts` entry becomes a separate context message. `block`
- * records a durable `prompt/blocked` and ends the claimed prompt's zero-step
- * turn as rejected. An `allow` returned by a listener is authoritative: a
- * listener wrapping `next()` preserves downstream `content` and
- * `additionalContexts` unless it intentionally replaces them.
+ * Prompt interception result. `allow.content` replaces the prompt. Each
+ * `additionalContexts` entry follows its declared placement: separate context
+ * message by default, or a prefix inside the prompt's user-role message.
+ * `block` records a durable `prompt/blocked` and ends the claimed prompt's
+ * zero-step turn as rejected. An `allow` returned by a listener is
+ * authoritative: a listener wrapping `next()` preserves downstream `content`
+ * and `additionalContexts` unless it intentionally replaces them.
  */
 type PromptDecision =
   | { kind: 'allow'; content?: ContentBlock[]; additionalContexts?: HookContext[] }
diff --git a/docs/core-data-structures/session.md b/docs/core-data-structures/session.md
index e115de01ec..089eabd71c 100644
--- a/docs/core-data-structures/session.md
+++ b/docs/core-data-structures/session.md
@@ -8,6 +8,18 @@ Source: [`packages/core/session/src/types.ts`](../../packages/core/session/src/t
 
 The append-only event types. Merge-extensible: a plugin declares extra event types via declaration merging — e.g. the [compaction seam](compaction.md) adds `compact/start` / `compact/summary` / `compact/end`, and `@deepseek-ai/dsh-hook-protocol` adds log-only `hook/invoked` / `hook/result` provenance for a hook bridge. Like `compact/*`, these are NOT `SurfaceEventType`s (no `surfaceOp`). The generated [persistence log event catalog](../persistence-catalog.md) enumerates every member — core and merged — with its payload, surface badge, and declaration site.
 
+```ts type-equiv
+/** Shared payload for ordinary and steering prompt messages. */
+interface PromptMessageData {
+  /** Exact model-facing blocks, including any baked prompt-prefix contexts. */
+  content: ContentBlock[]
+  /** Producer provenance for the direct prompt. */
+  source: MessageSource
+  /** Present only when prompt-prefix contexts were baked into `content`. */
+  envelope?: PromptMessageEnvelope
+}
+```
+
 ```ts type-equiv
 /**
  * The merge-extensible, append-only source of truth for an agent interaction.
@@ -35,7 +47,7 @@ interface SessionEventMap {
   /** Closes step `step` of turn `turn`. */
   'step/end': { turn: number; step: number }
   /** A user-visible prompt (the queued message claimed for this turn). */
-  'user/message': { content: ContentBlock[]; source: MessageSource }
+  'user/message': PromptMessageData
   /**
    * Durable record of a prompt veto and its reason. It is log-only: the blocked
    * prompt never enters the model-visible surface, and its turn runs zero steps.
@@ -83,7 +95,7 @@ interface SessionEventMap {
    */
   'tool/result': { turn: number; step: number; callId: CallId; content: ContentBlock[]; isError: boolean; error?: { name: string; code: string }; meta?: unknown }
   /** Steering content injected between steps of a running turn. */
-  'steering/message': { turn: number; content: ContentBlock[]; source: MessageSource }
+  'steering/message': PromptMessageData & { turn: number }
   /** Whole-list snapshot; latest write wins on replay. Log-only UI state; never derived history. */
   'todo/write': { todos: TodoItem[] }
   /**
@@ -94,6 +106,8 @@ interface SessionEventMap {
 }
 ```
 
+`PromptMessageData.content` is always the exact model-facing content. When attached context declares `prompt-prefix` placement, AgentLoop concatenates its blocks, a `## My request:` delimiter, and the effective direct prompt into that array. The optional model-hidden `envelope` retains `displayContent` plus ordered prefix-context source/metadata descriptors, so transcript, title, and re-reference consumers can present the human prompt without changing reconstructable history. `displayPromptContent()` performs that selection and falls back to `content` for ordinary and older events.
+
 ### `OutOfBandSessionEventMap` — narrow late-append opt-in
 
 `SessionEventMap` membership alone does not authorize an event outside the agent loop's ordinary lifecycle. An event owner declaration-merges the same key into this empty marker map before `ctx.sessions.appendOutOfBand()` accepts it; the derived type additionally excludes every surface event. An accepted update joins an open turn or receives a balanced, flushed zero-step turn.
@@ -438,11 +452,11 @@ declare class Session {
 
 `Session.deriveMessages()` projects the event log into the `Message[]` the model sees — cached (each surface node projected once, when first seen; a surface rewrite rebuilds) and frozen (a fresh array per call over shared, deep-frozen messages, so mutating logged history through a projection is unrepresentable). `deriveEventMessage(event)` is the per-node pure function the fold applies — public so external reconstructors and the dev invariant project a log prefix with exactly the same rules and cannot disagree with the cache. The projection rules:
 
-- `user/message` → a user message.
+- `user/message` → a user message carrying exact `content`; an optional envelope remains log-only display metadata.
 - `assistant/message` → an assistant message with the event's provider/model provenance and optional adapter-private replay state. Raw `assistant/chunk` events are replay/UI data and are **skipped** in derivation (the assembled message is authoritative). An **empty-content** `assistant/message` is also skipped — a max-tokens step cut off with no content still records an `assistant/message` to host its usage/provenance, but a content-less assistant turn must not enter the provider transcript.
 - `tool/result` → a user message carrying a `tool-result` block.
 - `context/message` → a user-role message carrying its `content` verbatim at its chronological position. Optional JSON `meta` remains in the event log and is never rendered.
-- `steering/message` → a user-role message carrying its content verbatim at its chronological position.
+- `steering/message` → a user-role message carrying exact `content` at its chronological position; an optional envelope remains log-only display metadata.
 
 Everything else (`turn/*`, `step/*`, plugin-owned `llm/retry`) is structural and does not project into a message. Token accounting reads per-step `assistant/chunk { type: 'usage' }` records and treats `assistant/message.usage` as the committed-step fallback when no usage chunk exists; failed model-request attempts have no assistant message, so their usage chunk is the durable accounting record. An operational error's step number is on `turn/end.reason` for `kind: 'error'`, with normalized `LlmFailure` facts for a final model-request failure and message/code for other live errors. Because this unreleased format intentionally has no compatibility promise, seed/load validation rejects request headers without provider+model and assistant messages without provider/model provenance instead of guessing a route for historical data.
 
diff --git a/docs/event-producer-consumer.md b/docs/event-producer-consumer.md
index cac3ff4fb7..cf2a5d7252 100644
--- a/docs/event-producer-consumer.md
+++ b/docs/event-producer-consumer.md
@@ -8,22 +8,22 @@ This matrix shows which packages dispatch each harness-owned event and which pac
 | Event | Mode | Declared in | Dispatchers | Listeners |
 | --- | --- | --- | --- | --- |
 | `agent-loop/config-start-failed` | `emit` | [`packages/core/agent-loop/src/index.ts:353`](../packages/core/agent-loop/src/index.ts) | [`agent-loop`](../packages/core/agent-loop) (`events.dispatch`) | [`tui`](../packages/ui/tui) |
-| `agent/cancel-requested` | `emit` | [`packages/core/agent/src/types.ts:210`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal-session`](../packages/goal/goal-session) |
-| `agent/created` | `emit` | [`packages/core/agent/src/types.ts:172`](../packages/core/agent/src/types.ts) | [`agent`](../packages/core/agent) (`events.dispatch`) | [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
-| `agent/disposed` | `emit` | [`packages/core/agent/src/types.ts:181`](../packages/core/agent/src/types.ts) | [`agent`](../packages/core/agent) (`events.dispatch`) | [`agent-loop`](../packages/core/agent-loop), [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
-| `agent/error` | `emit` | [`packages/core/agent/src/types.ts:358`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
-| `agent/post-step` | `serial` | [`packages/core/agent/src/types.ts:308`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`serial`) | [`compact-basic`](../packages/compact/compact-basic) |
-| `agent/pre-step` | `serial` | [`packages/core/agent/src/types.ts:239`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`serial`) | [`time-context`](../packages/context/time-context), [`user-approval`](../packages/ui/user-approval) |
-| `agent/prompt-submit` | `waterfall` | [`packages/core/agent/src/types.ts:255`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`acp`](../packages/ui/acp), [`goal-session`](../packages/goal/goal-session), [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex), [`repeat-tool-guard`](../packages/guard/repeat-tool-guard) |
-| `agent/queued` | `emit` | [`packages/core/agent/src/types.ts:200`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal-session`](../packages/goal/goal-session) |
-| `agent/request` | `waterfall` | [`packages/core/agent/src/types.ts:269`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`agent`](../packages/core/agent) |
-| `agent/request-error` | `waterfall` | [`packages/core/agent/src/types.ts:323`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`compact-basic`](../packages/compact/compact-basic), [`llm-retry`](../packages/llm/llm-retry) |
-| `agent/session-prefix` | `waterfall` | [`packages/core/agent/src/types.ts:284`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`tool-skill`](../packages/skill/tool-skill), [`workspace-context`](../packages/context/workspace-context) |
-| `agent/session-start` | `emit` | [`packages/core/agent/src/types.ts:223`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal`](../packages/goal/goal), [`goal-session`](../packages/goal/goal-session), [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex) |
-| `agent/status` | `emit` | [`packages/core/agent/src/types.ts:190`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`agent`](../packages/core/agent), [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
-| `agent/step-result` | `waterfall` | [`packages/core/agent/src/types.ts:296`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | - |
-| `agent/turn-continuation` | `waterfall` | [`packages/core/agent/src/types.ts:334`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex) |
-| `agent/turn-stop` | `serial` | [`packages/core/agent/src/types.ts:345`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`serial`) | [`subagent-inprocess`](../packages/subagent/subagent-inprocess), [`tool-goal`](../packages/goal/tool-goal) |
+| `agent/cancel-requested` | `emit` | [`packages/core/agent/src/types.ts:217`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal-session`](../packages/goal/goal-session) |
+| `agent/created` | `emit` | [`packages/core/agent/src/types.ts:179`](../packages/core/agent/src/types.ts) | [`agent`](../packages/core/agent) (`events.dispatch`) | [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
+| `agent/disposed` | `emit` | [`packages/core/agent/src/types.ts:188`](../packages/core/agent/src/types.ts) | [`agent`](../packages/core/agent) (`events.dispatch`) | [`agent-loop`](../packages/core/agent-loop), [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
+| `agent/error` | `emit` | [`packages/core/agent/src/types.ts:365`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
+| `agent/post-step` | `serial` | [`packages/core/agent/src/types.ts:315`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`serial`) | [`compact-basic`](../packages/compact/compact-basic) |
+| `agent/pre-step` | `serial` | [`packages/core/agent/src/types.ts:246`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`serial`) | [`time-context`](../packages/context/time-context), [`user-approval`](../packages/ui/user-approval) |
+| `agent/prompt-submit` | `waterfall` | [`packages/core/agent/src/types.ts:262`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`acp`](../packages/ui/acp), [`goal-session`](../packages/goal/goal-session), [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex), [`repeat-tool-guard`](../packages/guard/repeat-tool-guard) |
+| `agent/queued` | `emit` | [`packages/core/agent/src/types.ts:207`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal-session`](../packages/goal/goal-session) |
+| `agent/request` | `waterfall` | [`packages/core/agent/src/types.ts:276`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`agent`](../packages/core/agent) |
+| `agent/request-error` | `waterfall` | [`packages/core/agent/src/types.ts:330`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`compact-basic`](../packages/compact/compact-basic), [`llm-retry`](../packages/llm/llm-retry) |
+| `agent/session-prefix` | `waterfall` | [`packages/core/agent/src/types.ts:291`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`tool-skill`](../packages/skill/tool-skill), [`workspace-context`](../packages/context/workspace-context) |
+| `agent/session-start` | `emit` | [`packages/core/agent/src/types.ts:230`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal`](../packages/goal/goal), [`goal-session`](../packages/goal/goal-session), [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex) |
+| `agent/status` | `emit` | [`packages/core/agent/src/types.ts:197`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`agent`](../packages/core/agent), [`goal-session`](../packages/goal/goal-session), [`tui`](../packages/ui/tui) |
+| `agent/step-result` | `waterfall` | [`packages/core/agent/src/types.ts:303`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | - |
+| `agent/turn-continuation` | `waterfall` | [`packages/core/agent/src/types.ts:341`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex) |
+| `agent/turn-stop` | `serial` | [`packages/core/agent/src/types.ts:352`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`serial`) | [`subagent-inprocess`](../packages/subagent/subagent-inprocess), [`tool-goal`](../packages/goal/tool-goal) |
 | `approval/request` | `waterfall` | [`packages/ui/user-approval/src/index.ts:31`](../packages/ui/user-approval/src/index.ts) | [`user-approval`](../packages/ui/user-approval) (`waterfall`) | [`acp`](../packages/ui/acp) |
 | `commands/change` | `emit` | [`packages/ui/commands/src/index.ts:83`](../packages/ui/commands/src/index.ts) | [`commands`](../packages/ui/commands) (`events.dispatch`) | [`acp`](../packages/ui/acp), [`tui`](../packages/ui/tui) |
 | `fs/edit-intent` | `waterfall` | [`packages/fs/fs/src/index.ts:62`](../packages/fs/fs/src/index.ts) | [`tool-fs`](../packages/fs/tool-fs) (`waterfall`) | [`fs-policy`](../packages/fs/fs-policy) |
@@ -31,10 +31,10 @@ This matrix shows which packages dispatch each harness-owned event and which pac
 | `fs/write-intent` | `waterfall` | [`packages/fs/fs/src/index.ts:54`](../packages/fs/fs/src/index.ts) | [`tool-fs`](../packages/fs/tool-fs) (`waterfall`) | [`fs-policy`](../packages/fs/fs-policy) |
 | `goal/changed` | `emit` | [`packages/goal/goal/src/types.ts:167`](../packages/goal/goal/src/types.ts) | [`goal`](../packages/goal/goal) (`emit`) | [`goal-session`](../packages/goal/goal-session) |
 | `llm/stream` | `waterfall` | [`packages/llm/llm/src/index.ts:52`](../packages/llm/llm/src/index.ts) | [`llm`](../packages/llm/llm) (`waterfall`) | [`agent-loop`](../packages/core/agent-loop), [`llm`](../packages/llm/llm), [`llm-replay`](../packages/support/llm-replay), [`session-title`](../packages/session-title/session-title) |
-| `session/created` | `emit` | [`packages/core/session/src/index.ts:68`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`compact`](../packages/compact/compact), [`goal`](../packages/goal/goal), [`hook-protocol`](../packages/hooks/hook-protocol), [`jsonrpc`](../packages/ui/jsonrpc), [`llm-retry`](../packages/llm/llm-retry), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`user-approval`](../packages/ui/user-approval) |
-| `session/disposed` | `emit` | [`packages/core/session/src/index.ts:78`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`agent-loop`](../packages/core/agent-loop), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-title`](../packages/session-title/session-title) |
-| `session/event` | `emit` | [`packages/core/session/src/index.ts:90`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`acp`](../packages/ui/acp), [`cli-demo`](../packages/examples/cli-demo), [`compact`](../packages/compact/compact), [`goal`](../packages/goal/goal), [`goal-session`](../packages/goal/goal-session), [`hook-protocol`](../packages/hooks/hook-protocol), [`jsonrpc`](../packages/ui/jsonrpc), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-title`](../packages/session-title/session-title), [`token-meter`](../packages/llm/token-meter), [`tui`](../packages/ui/tui), [`user-approval`](../packages/ui/user-approval), [`workspace-context`](../packages/context/workspace-context) |
-| `session/flush` | `parallel` | [`packages/core/session/src/index.ts:100`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`session-persistence`](../packages/session-persistence/session-persistence) |
+| `session/created` | `emit` | [`packages/core/session/src/index.ts:77`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`compact`](../packages/compact/compact), [`goal`](../packages/goal/goal), [`hook-protocol`](../packages/hooks/hook-protocol), [`jsonrpc`](../packages/ui/jsonrpc), [`llm-retry`](../packages/llm/llm-retry), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`user-approval`](../packages/ui/user-approval) |
+| `session/disposed` | `emit` | [`packages/core/session/src/index.ts:87`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`agent-loop`](../packages/core/agent-loop), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-title`](../packages/session-title/session-title) |
+| `session/event` | `emit` | [`packages/core/session/src/index.ts:99`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`acp`](../packages/ui/acp), [`cli-demo`](../packages/examples/cli-demo), [`compact`](../packages/compact/compact), [`goal`](../packages/goal/goal), [`goal-session`](../packages/goal/goal-session), [`hook-protocol`](../packages/hooks/hook-protocol), [`jsonrpc`](../packages/ui/jsonrpc), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-title`](../packages/session-title/session-title), [`token-meter`](../packages/llm/token-meter), [`tui`](../packages/ui/tui), [`user-approval`](../packages/ui/user-approval), [`workspace-context`](../packages/context/workspace-context) |
+| `session/flush` | `parallel` | [`packages/core/session/src/index.ts:109`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`session-persistence`](../packages/session-persistence/session-persistence) |
 | `subagent/end` | `emit` | [`packages/subagent/subagent/src/index.ts:139`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`hooks-claude`](../packages/hooks/hooks-claude), [`jsonrpc`](../packages/ui/jsonrpc), [`subagent`](../packages/subagent/subagent) |
 | `subagent/provider-added` | `emit` | [`packages/subagent/subagent/src/index.ts:113`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`emit`) | [`subagent`](../packages/subagent/subagent), [`tool-subagent`](../packages/subagent/tool-subagent) |
 | `subagent/provider-removed` | `emit` | [`packages/subagent/subagent/src/index.ts:119`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`subagent`](../packages/subagent/subagent), [`tool-subagent`](../packages/subagent/tool-subagent) |
diff --git a/docs/module-graph.md b/docs/module-graph.md
index 828ae59c79..f60663f619 100644
--- a/docs/module-graph.md
+++ b/docs/module-graph.md
@@ -496,6 +496,7 @@ flowchart TD
   pkg_acp --> pkg_sandbox
   pkg_acp --> pkg_session
   pkg_acp --> pkg_session_persistence
+  pkg_acp --> pkg_session_query
   pkg_acp --> pkg_session_reference
   pkg_acp --> pkg_session_title
   pkg_acp --> pkg_system_prompt
@@ -753,7 +754,7 @@ flowchart TD
 | [`tool-cordis`](../packages/cordis/tool-cordis) | `cordis` | [`invariants`](../packages/support/invariants), [`scope`](../packages/core/scope), [`tools`](../packages/core/tools) |
 | [`hooks-codex`](../packages/hooks/hooks-codex) | `hooks` | [`agent`](../packages/core/agent), [`hook-protocol`](../packages/hooks/hook-protocol), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`tools`](../packages/core/tools) |
 | [`agent-loop-testkit`](../packages/support/agent-loop-testkit) | `support` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
-| [`acp`](../packages/ui/acp) | `ui` | [`agent`](../packages/core/agent), [`bash`](../packages/bash/bash), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`llm-retry`](../packages/llm/llm-retry), [`permission`](../packages/ui/permission), [`sandbox`](../packages/sandbox/sandbox), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-reference`](../packages/context/session-reference), [`session-title`](../packages/session-title/session-title), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools), [`user-approval`](../packages/ui/user-approval), [`user-interaction`](../packages/ui/user-interaction) |
+| [`acp`](../packages/ui/acp) | `ui` | [`agent`](../packages/core/agent), [`bash`](../packages/bash/bash), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`llm-retry`](../packages/llm/llm-retry), [`permission`](../packages/ui/permission), [`sandbox`](../packages/sandbox/sandbox), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-query`](../packages/session-query/session-query), [`session-reference`](../packages/context/session-reference), [`session-title`](../packages/session-title/session-title), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools), [`user-approval`](../packages/ui/user-approval), [`user-interaction`](../packages/ui/user-interaction) |
 | [`tool-ask-user`](../packages/ui/tool-ask-user) | `ui` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction) |
 | [`workspace-context`](../packages/context/workspace-context) | `context` | [`agent`](../packages/core/agent), [`fs`](../packages/fs/fs), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`paths`](../packages/util/paths), [`session`](../packages/core/session), [`tools`](../packages/core/tools) |
 | [`repeat-tool-guard`](../packages/guard/repeat-tool-guard) | `guard` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`tools`](../packages/core/tools) |
diff --git a/docs/persistence-catalog.md b/docs/persistence-catalog.md
index 9793d262f5..a0774d1eb9 100644
--- a/docs/persistence-catalog.md
+++ b/docs/persistence-catalog.md
@@ -79,7 +79,7 @@ export type SessionEvent<T extends SessionEventType = SessionEventType> = {
 }[T]
 ```
 
-Sources: [`packages/core/session/src/types.ts:276`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:289`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:319`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:351`](../packages/core/session/src/types.ts)
+Sources: [`packages/core/session/src/types.ts:307`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:320`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:350`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:382`](../packages/core/session/src/types.ts)
 
 ## Events
 
@@ -151,7 +151,7 @@ Source: [`packages/ui/user-approval/src/index.ts:68`](../packages/ui/user-approv
 
 Types: [StreamChunk](core-data-structures/llm-streaming.md)
 
-Source: [`packages/core/session/src/types.ts:232`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:263`](../packages/core/session/src/types.ts)
 
 #### `assistant/message` — surface
 
@@ -167,7 +167,7 @@ Source: [`packages/core/session/src/types.ts:232`](../packages/core/session/src/
 
 Types: [ContentBlock](core-data-structures/core.md) · [TokenUsage](core-data-structures/llm-streaming.md)
 
-Source: [`packages/core/session/src/types.ts:239`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:270`](../packages/core/session/src/types.ts)
 
 ### `compact/*`
 
@@ -246,7 +246,7 @@ Source: [`packages/compact/compact/src/types.ts:22`](../packages/compact/compact
 
 Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)
 
-Source: [`packages/core/session/src/types.ts:226`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:257`](../packages/core/session/src/types.ts)
 
 ### `hook/*`
 
@@ -342,7 +342,7 @@ Source: [`packages/ui/permission/src/index.ts:36`](../packages/ui/permission/src
 
 Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)
 
-Source: [`packages/core/session/src/types.ts:214`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:245`](../packages/core/session/src/types.ts)
 
 ### `request/*`
 
@@ -356,7 +356,7 @@ Source: [`packages/core/session/src/types.ts:214`](../packages/core/session/src/
 'request/header': { header: EpochHeader; reason: RequestHeaderReason }
 ```
 
-Source: [`packages/core/session/src/types.ts:264`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:295`](../packages/core/session/src/types.ts)
 
 ### `sandbox/*`
 
@@ -390,7 +390,7 @@ Source: [`packages/sandbox/sandbox-policy/src/session-mode.ts:34`](../packages/s
 
 Types: [SessionTitleEventData](core-data-structures/session-title.md)
 
-Source: [`packages/session-title/session-title/src/index.ts:95`](../packages/session-title/session-title/src/index.ts)
+Source: [`packages/session-title/session-title/src/index.ts:96`](../packages/session-title/session-title/src/index.ts)
 
 #### `session/title-llm-request` — log-only
 
@@ -409,12 +409,10 @@ Source: [`packages/session-title/session-title-llm/src/index.ts:44`](../packages
 
 ```ts persistence-catalog
 /** Steering content injected between steps of a running turn. */
-'steering/message': { turn: number; content: ContentBlock[]; source: MessageSource }
+'steering/message': PromptMessageData & { turn: number }
 ```
 
-Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)
-
-Source: [`packages/core/session/src/types.ts:257`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:288`](../packages/core/session/src/types.ts)
 
 ### `step/*`
 
@@ -425,7 +423,7 @@ Source: [`packages/core/session/src/types.ts:257`](../packages/core/session/src/
 'step/end': { turn: number; step: number }
 ```
 
-Source: [`packages/core/session/src/types.ts:207`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:238`](../packages/core/session/src/types.ts)
 
 #### `step/start` — log-only
 
@@ -434,7 +432,7 @@ Source: [`packages/core/session/src/types.ts:207`](../packages/core/session/src/
 'step/start': { turn: number; step: number }
 ```
 
-Source: [`packages/core/session/src/types.ts:205`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:236`](../packages/core/session/src/types.ts)
 
 ### `todo/*`
 
@@ -447,7 +445,7 @@ Source: [`packages/core/session/src/types.ts:205`](../packages/core/session/src/
 
 Types: [TodoItem](core-data-structures/session.md)
 
-Source: [`packages/core/session/src/types.ts:259`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:290`](../packages/core/session/src/types.ts)
 
 ### `tool/*`
 
@@ -464,7 +462,7 @@ Source: [`packages/core/session/src/types.ts:259`](../packages/core/session/src/
 
 Types: [CallId](core-data-structures/core.md)
 
-Source: [`packages/core/session/src/types.ts:245`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:276`](../packages/core/session/src/types.ts)
 
 #### `tool/code-dispatch` — log-only
 
@@ -508,7 +506,7 @@ Source: [`packages/core/tools/src/code-mode.ts:34`](../packages/core/tools/src/c
 
 Types: [CallId](core-data-structures/core.md) · [ContentBlock](core-data-structures/core.md)
 
-Source: [`packages/core/session/src/types.ts:255`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:286`](../packages/core/session/src/types.ts)
 
 ### `turn/*`
 
@@ -526,7 +524,7 @@ Source: [`packages/core/session/src/types.ts:255`](../packages/core/session/src/
 
 Types: [TurnEndReason](core-data-structures/session.md)
 
-Source: [`packages/core/session/src/types.ts:203`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:234`](../packages/core/session/src/types.ts)
 
 #### `turn/start` — log-only
 
@@ -542,7 +540,7 @@ Source: [`packages/core/session/src/types.ts:203`](../packages/core/session/src/
 
 Types: [TurnTrigger](core-data-structures/session.md)
 
-Source: [`packages/core/session/src/types.ts:196`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:227`](../packages/core/session/src/types.ts)
 
 ### `user/*`
 
@@ -550,9 +548,7 @@ Source: [`packages/core/session/src/types.ts:196`](../packages/core/session/src/
 
 ```ts persistence-catalog
 /** A user-visible prompt (the queued message claimed for this turn). */
-'user/message': { content: ContentBlock[]; source: MessageSource }
+'user/message': PromptMessageData
 ```
 
-Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)
-
-Source: [`packages/core/session/src/types.ts:209`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:240`](../packages/core/session/src/types.ts)
diff --git a/examples/acp-agent/tests/goal-snapshots/goal-session/stdout.expected.jsonl b/examples/acp-agent/tests/goal-snapshots/goal-session/stdout.expected.jsonl
index 809c9511a5..8f3d2d88c3 100644
--- a/examples/acp-agent/tests/goal-snapshots/goal-session/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/goal-snapshots/goal-session/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Create a durable two-round goal","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/advanced-toolchain/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/advanced-toolchain/stdout.expected.jsonl
index 52f0bd6fc8..2ea201e45e 100644
--- a/examples/acp-agent/tests/snapshots/advanced-toolchain/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/advanced-toolchain/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Run this advanced flow exactly","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/bash-spill/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/bash-spill/stdout.expected.jsonl
index 888df14a4b..8569109fb6 100644
--- a/examples/acp-agent/tests/snapshots/bash-spill/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/bash-spill/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/both-mode-turn/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/both-mode-turn/stdout.expected.jsonl
index 5cbeaad1e9..72c40a6406 100644
--- a/examples/acp-agent/tests/snapshots/both-mode-turn/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/both-mode-turn/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Call the run_code tool (NOT","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/cancel-tool-calls/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/cancel-tool-calls/stdout.expected.jsonl
index 5c30d144c0..a2fb4342cc 100644
--- a/examples/acp-agent/tests/snapshots/cancel-tool-calls/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/cancel-tool-calls/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Run two shell commands: wait","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/cancel/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/cancel/stdout.expected.jsonl
index bb775c6c90..87b97d98c5 100644
--- a/examples/acp-agent/tests/snapshots/cancel/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/cancel/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Start a long task; this","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/code-mode-turn/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/code-mode-turn/stdout.expected.jsonl
index d30932e4f2..ec9949f734 100644
--- a/examples/acp-agent/tests/snapshots/code-mode-turn/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/code-mode-turn/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Using ONE run_code program: call","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/code-mode-workspace-context/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/code-mode-workspace-context/stdout.expected.jsonl
index 36aee81d82..8d1b4928e4 100644
--- a/examples/acp-agent/tests/snapshots/code-mode-workspace-context/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/code-mode-workspace-context/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Using ONE run_code program, call","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/config-options/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/config-options/stdout.expected.jsonl
index eddfde0332..79576f4a07 100644
--- a/examples/acp-agent/tests/snapshots/config-options/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/config-options/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","id":3,"result":{"configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"workspace-write","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
diff --git a/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/session.jsonl b/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/session.jsonl
index d3d6f361b2..bd13d3b146 100644
--- a/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/session.jsonl
+++ b/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/session.jsonl
@@ -11,7 +11,7 @@
 {"type":"assistant/chunk","seq":9,"time":1783951000009,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
 {"type":"assistant/message","seq":10,"time":1784449176722,"data":{"turn":1,"step":1,"content":[{"type":"tool-call","id":"inspect-tools-api","name":"cordis_inspect","arguments":"{\"what\":\"api\",\"name\":\"tools\"}"}],"provenance":{"provider":"deepseek","model":"deepseek-v4-flash"},"usage":{"inputTokens":3,"outputTokens":3}},"sourceEventSeqs":[5,6,7,8,9],"surfaceOp":"append"}
 {"type":"tool/call","seq":11,"time":1784449176722,"data":{"turn":1,"step":1,"callId":"inspect-tools-api","name":"cordis_inspect","arguments":"{\"what\":\"api\",\"name\":\"tools\"}"}}
-{"type":"tool/result","seq":12,"time":1784449176732,"data":{"turn":1,"step":1,"callId":"inspect-tools-api","content":[{"type":"text","text":"## api\n- tools — Tool registry and execution pipeline.\n    /**\n     * Register globally or in the calling agent scope. Scoped tools shadow\n     * globals; duplicates within one layer and the reserved `run_code` name fail.\n     * @param definition - the tool schema, execution, and optional presentation functions.\n     * @returns the exact disposer that unregisters the tool.\n     */\n    register(definition: ToolDefinition): () => void\n    /**\n     * Restrict global tools for the calling agent scope. Empty filters, unknown\n     * names, scope-local names, and reserved transport names fail. Restrictions\n     * intersect; scoped registrations remain visible.\n     * @param filter - global-surface mask: `allow` (keep only) and/or `deny` (remove).\n     * @returns the exact disposer that lifts this restriction.\n     */\n    restrict(filter: ToolRestriction): () => void\n    /**\n     * Register a monotonic guard after the extensible `tools/pre-execute`\n     * waterfall. A plain-context guard applies globally; one registered through\n     * `agent.ctx` applies only to that agent. Any matching guard may deny by\n     * returning a reason, while no guard can force-allow a call another guard\n     * denied. The exact effect disposer is returned for ordered ownership and\n     * HMR cleanup.\n     * @param guard - synchronous check; a returned string denies the execution.\n     * @returns the exact disposer that unregisters the guard.\n     */\n    guard(guard: ToolGuard): () => void\n    /**\n     * Look up a tool as one scope sees it (scoped\n     * shadows global; a restricted-away global reads as absent). Presenters pass\n     * the calling agent so the rendered card matches the definition that\n     * actually executed.\n     * @param name - the tool name as registered.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns the definition the scope resolves, or undefined when none is visible.\n     */\n    get(name: string, scope?: ScopeKey): ToolDefinition | undefined\n    /**\n     * Project visible definitions onto the allowlisted model-facing schema fields,\n     * excluding execution and presentation callbacks.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns one deep-cloned schema per visible tool.\n     */\n    schemas(scope?: ScopeKey): ToolSchema[]\n    /**\n     * Classify a pending call through the caller's visible tool definition. Only\n     * an exact `true` is parallel; unknown, hidden, undeclared, invalid, or\n     * throwing classifiers are exclusive.\n     * @param exec - call name, parsed arguments, and optional agent scope.\n     * @returns the fail-closed scheduling mode.\n     */\n    executionMode(exec: ToolExecutionInput): ToolExecutionMode\n    /**\n     * Execute through pre-policy, guards, around-dispatch, post-policy, and final\n     * notification. Tool and listener failures resolve as materialized error\n     * results; an invisible tool reports `UNKNOWN_TOOL`. The returned outcome is\n     * the same lossless, frozen snapshot final observers receive. Cancellation\n     * arriving after entry and before final result materialization skips a\n     * not-yet-started body with `ABORTED_BEFORE_DISPATCH` or replaces a\n     * successful started outcome with `ABORTED`; already-started work is still\n     * drained and may retain a tool-owned structured error.\n     * @param exec - the typed same-process call input. The registry assigns its\n     *   correlation token before policy begins.\n     * @returns the materialized final result.\n     */\n    async execute(exec: ToolExecutionInput): Promise<ToolExecutionResult>\ntype shapes (referenced by the signatures above — read these before assuming a field is a string):\n    export interface Agent {\n        readonly id: SessionId;\n        readonly options: AgentOptions;\n        readonly session: Session;\n        readonly status: AgentStatus;\n        readonly ctx: Context;\n        send(content: ContentBlock[], options?: SendOptions): void;\n        steer(content: ContentBlock[], options?: SendOptions): void;\n        inject(content: ContentBlock[], options?: InjectOptions): void;\n        cancel(cause?: AgentCancelCause): void;\n        whenIdle(): Promise<void>;\n    }\n    export type AgentCancelCause = {\n        readonly kind: 'user';\n    } | {\n        readonly kind: 'parent';\n    };\n    export interface AgentOptions {\n        provider?: string;\n        model?: string;\n    }\n    export type AgentStatus = 'idle' | 'running' | 'disposed';\n    export type Branded<B extends string> = string & {\n        readonly [BRAND]: B;\n    };\n    export type CallId = Branded<'CallId'>;\n    export interface DiffCallView {\n        card: 'diff';\n        title: string;\n        diffs: FileDiff[];\n        locations?: FileLocation[];\n    }\n    export interface DiffResultView {\n        card: 'diff';\n        title?: string;\n        diffs: FileDiff[];\n    }\n    export interface FileDiff {\n        path: string;\n        oldText: string | null;\n        newText: string;\n    }\n    export interface FileLocation {\n        path: string;\n        line?: number;\n    }\n    export interface GenericCallView {\n        card: 'generic';\n        title: string;\n        kind?: ToolCallKind;\n        rawInput?: unknown;\n        content?: ContentBlock[];\n        locations?: FileLocation[];\n    }\n    export interface GenericResultView {\n        card: 'generic';\n        title?: string;\n        content?: ContentBlock[];\n    }\n    export interface HookContext {\n        content: ContentBlock[];\n        source: MessageSource;\n        meta?: JsonValue;\n    }\n    export interface InjectOptions extends Omit<SendOptions, 'contexts'> {\n        meta?: JsonValue;\n    }\n    export type JsonValue = null | boolean | number | string | JsonValue[] | {\n        [key: string]: JsonValue;\n    };\n    export type MessageSource = MessageSourceMap[keyof MessageSourceMap];\n    export interface MessageSourceMap {\n        user: {\n            kind: 'user';\n        };\n        plugin: {\n            kind: 'plugin';\n            plugin: string;\n        };\n    }\n    export type ScopeKey = object;\n    export interface SendOptions {\n        source?: MessageSource;\n        contexts?: HookContext[];\n    }\n    export type SessionId = Branded<'SessionId'>;\n    export interface TerminalCallView {\n        card: 'terminal';\n        title: string;\n        description?: string;\n        cwd?: string;\n    }\n    export interface TerminalResultView {\n        card: 'terminal';\n        title?: string;\n        output?: string;\n        exitCode?: number;\n        signal?: string;\n    }\n    export type ToolCallKind = 'read' | 'edit' | 'delete' | 'move' | 'search' | 'execute' | 'fetch' | 'other';\n    export type ToolCallView = GenericCallView | TerminalCallView | DiffCallView;\n    export interface ToolDefinition extends ToolSchema {\n        execute(args: unknown, exec: ToolRunContext): Promise<ToolExecuteReturn>;\n        timeoutMs?: number;\n        isConcurrencySafe?(args: unknown): boolean;\n        presentCall?(args: unknown): ToolCallView | undefined;\n        presentResult?(args: unknown, result: ToolResult): ToolResultView | undefined;\n    }\n    export interface ToolErrorInfo {\n        name: string;\n        code: string;\n    }\n    export type ToolExecuteReturn = ContentBlock[] | {\n        content: ContentBlock[];\n        meta?: unknown;\n    };\n    export interface ToolExecution extends ToolExecutionInput {\n        readonly token: ToolExecutionToken;\n    }\n    export interface ToolExecutionInput {\n        readonly callId: CallId;\n        readonly name: string;\n        readonly arguments: unknown;\n        readonly agent?: Agent;\n        readonly parent?: ToolExecutionToken;\n        readonly signal: AbortSignal;\n    }\n    export type ToolExecutionMode = {\n        kind: 'parallel';\n    } | {\n        kind: 'exclusive';\n    };\n    export interface ToolExecutionResult {\n        content: ContentBlock[];\n        isError: boolean;\n        error?: ToolErrorInfo;\n        additionalContexts?: HookContext[];\n        meta?: unknown;\n    }\n    export type ToolExecutionToken = symbol & {\n        readonly [toolExecutionTokenBrand]: true;\n    };\n    export type ToolGuard = (execution: Readonly<ToolExecution>) => string | undefined;\n    export interface ToolRestriction {\n        readonly allow?: readonly string[];\n        readonly deny?: readonly string[];\n    }\n    export interface ToolResult {\n        content: ContentBlock[];\n        isError: boolean;\n        meta?: unknown;\n    }\n    export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView;\n    export interface ToolRunContext extends ToolExecution {\n        deferContext(context: HookContext): void;\n    }\n    export interface ToolSchema {\n        name: string;\n        description: string;\n        parameters: Record<string, unknown>;\n    }"}],"isError":false},"sourceEventSeqs":[11],"surfaceOp":"append"}
+{"type":"tool/result","seq":12,"time":1784449176732,"data":{"turn":1,"step":1,"callId":"inspect-tools-api","content":[{"type":"text","text":"## api\n- tools — Tool registry and execution pipeline.\n    /**\n     * Register globally or in the calling agent scope. Scoped tools shadow\n     * globals; duplicates within one layer and the reserved `run_code` name fail.\n     * @param definition - the tool schema, execution, and optional presentation functions.\n     * @returns the exact disposer that unregisters the tool.\n     */\n    register(definition: ToolDefinition): () => void\n    /**\n     * Restrict global tools for the calling agent scope. Empty filters, unknown\n     * names, scope-local names, and reserved transport names fail. Restrictions\n     * intersect; scoped registrations remain visible.\n     * @param filter - global-surface mask: `allow` (keep only) and/or `deny` (remove).\n     * @returns the exact disposer that lifts this restriction.\n     */\n    restrict(filter: ToolRestriction): () => void\n    /**\n     * Register a monotonic guard after the extensible `tools/pre-execute`\n     * waterfall. A plain-context guard applies globally; one registered through\n     * `agent.ctx` applies only to that agent. Any matching guard may deny by\n     * returning a reason, while no guard can force-allow a call another guard\n     * denied. The exact effect disposer is returned for ordered ownership and\n     * HMR cleanup.\n     * @param guard - synchronous check; a returned string denies the execution.\n     * @returns the exact disposer that unregisters the guard.\n     */\n    guard(guard: ToolGuard): () => void\n    /**\n     * Look up a tool as one scope sees it (scoped\n     * shadows global; a restricted-away global reads as absent). Presenters pass\n     * the calling agent so the rendered card matches the definition that\n     * actually executed.\n     * @param name - the tool name as registered.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns the definition the scope resolves, or undefined when none is visible.\n     */\n    get(name: string, scope?: ScopeKey): ToolDefinition | undefined\n    /**\n     * Project visible definitions onto the allowlisted model-facing schema fields,\n     * excluding execution and presentation callbacks.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns one deep-cloned schema per visible tool.\n     */\n    schemas(scope?: ScopeKey): ToolSchema[]\n    /**\n     * Classify a pending call through the caller's visible tool definition. Only\n     * an exact `true` is parallel; unknown, hidden, undeclared, invalid, or\n     * throwing classifiers are exclusive.\n     * @param exec - call name, parsed arguments, and optional agent scope.\n     * @returns the fail-closed scheduling mode.\n     */\n    executionMode(exec: ToolExecutionInput): ToolExecutionMode\n    /**\n     * Execute through pre-policy, guards, around-dispatch, post-policy, and final\n     * notification. Tool and listener failures resolve as materialized error\n     * results; an invisible tool reports `UNKNOWN_TOOL`. The returned outcome is\n     * the same lossless, frozen snapshot final observers receive. Cancellation\n     * arriving after entry and before final result materialization skips a\n     * not-yet-started body with `ABORTED_BEFORE_DISPATCH` or replaces a\n     * successful started outcome with `ABORTED`; already-started work is still\n     * drained and may retain a tool-owned structured error.\n     * @param exec - the typed same-process call input. The registry assigns its\n     *   correlation token before policy begins.\n     * @returns the materialized final result.\n     */\n    async execute(exec: ToolExecutionInput): Promise<ToolExecutionResult>\ntype shapes (referenced by the signatures above — read these before assuming a field is a string):\n    export interface Agent {\n        readonly id: SessionId;\n        readonly options: AgentOptions;\n        readonly session: Session;\n        readonly status: AgentStatus;\n        readonly ctx: Context;\n        send(content: ContentBlock[], options?: SendOptions): void;\n        steer(content: ContentBlock[], options?: SendOptions): void;\n        inject(content: ContentBlock[], options?: InjectOptions): void;\n        cancel(cause?: AgentCancelCause): void;\n        whenIdle(): Promise<void>;\n    }\n    export type AgentCancelCause = {\n        readonly kind: 'user';\n    } | {\n        readonly kind: 'parent';\n    };\n    export interface AgentOptions {\n        provider?: string;\n        model?: string;\n    }\n    export type AgentStatus = 'idle' | 'running' | 'disposed';\n    export type Branded<B extends string> = string & {\n        readonly [BRAND]: B;\n    };\n    export type CallId = Branded<'CallId'>;\n    export interface DiffCallView {\n        card: 'diff';\n        title: string;\n        diffs: FileDiff[];\n        locations?: FileLocation[];\n    }\n    export interface DiffResultView {\n        card: 'diff';\n        title?: string;\n        diffs: FileDiff[];\n    }\n    export interface FileDiff {\n        path: string;\n        oldText: string | null;\n        newText: string;\n    }\n    export interface FileLocation {\n        path: string;\n        line?: number;\n    }\n    export interface GenericCallView {\n        card: 'generic';\n        title: string;\n        kind?: ToolCallKind;\n        rawInput?: unknown;\n        content?: ContentBlock[];\n        locations?: FileLocation[];\n    }\n    export interface GenericResultView {\n        card: 'generic';\n        title?: string;\n        content?: ContentBlock[];\n    }\n    export interface HookContext {\n        content: ContentBlock[];\n        source: MessageSource;\n        placement?: 'separate' | 'prompt-prefix';\n        meta?: JsonValue;\n    }\n    export interface InjectOptions extends Omit<SendOptions, 'contexts'> {\n        meta?: JsonValue;\n    }\n    export type JsonValue = null | boolean | number | string | JsonValue[] | {\n        [key: string]: JsonValue;\n    };\n    export type MessageSource = MessageSourceMap[keyof MessageSourceMap];\n    export interface MessageSourceMap {\n        user: {\n            kind: 'user';\n        };\n        plugin: {\n            kind: 'plugin';\n            plugin: string;\n        };\n    }\n    export type ScopeKey = object;\n    export interface SendOptions {\n        source?: MessageSource;\n        contexts?: HookContext[];\n    }\n    export type SessionId = Branded<'SessionId'>;\n    export interface TerminalCallView {\n        card: 'terminal';\n        title: string;\n        description?: string;\n        cwd?: string;\n    }\n    export interface TerminalResultView {\n        card: 'terminal';\n        title?: string;\n        output?: string;\n        exitCode?: number;\n        signal?: string;\n    }\n    export type ToolCallKind = 'read' | 'edit' | 'delete' | 'move' | 'search' | 'execute' | 'fetch' | 'other';\n    export type ToolCallView = GenericCallView | TerminalCallView | DiffCallView;\n    export interface ToolDefinition extends ToolSchema {\n        execute(args: unknown, exec: ToolRunContext): Promise<ToolExecuteReturn>;\n        timeoutMs?: number;\n        isConcurrencySafe?(args: unknown): boolean;\n        presentCall?(args: unknown): ToolCallView | undefined;\n        presentResult?(args: unknown, result: ToolResult): ToolResultView | undefined;\n    }\n    export interface ToolErrorInfo {\n        name: string;\n        code: string;\n    }\n    export type ToolExecuteReturn = ContentBlock[] | {\n        content: ContentBlock[];\n        meta?: unknown;\n    };\n    export interface ToolExecution extends ToolExecutionInput {\n        readonly token: ToolExecutionToken;\n    }\n    export interface ToolExecutionInput {\n        readonly callId: CallId;\n        readonly name: string;\n        readonly arguments: unknown;\n        readonly agent?: Agent;\n        readonly parent?: ToolExecutionToken;\n        readonly signal: AbortSignal;\n    }\n    export type ToolExecutionMode = {\n        kind: 'parallel';\n    } | {\n        kind: 'exclusive';\n    };\n    export interface ToolExecutionResult {\n        content: ContentBlock[];\n        isError: boolean;\n        error?: ToolErrorInfo;\n        additionalContexts?: HookContext[];\n        meta?: unknown;\n    }\n    export type ToolExecutionToken = symbol & {\n        readonly [toolExecutionTokenBrand]: true;\n    };\n    export type ToolGuard = (execution: Readonly<ToolExecution>) => string | undefined;\n    export interface ToolRestriction {\n        readonly allow?: readonly string[];\n        readonly deny?: readonly string[];\n    }\n    export interface ToolResult {\n        content: ContentBlock[];\n        isError: boolean;\n        meta?: unknown;\n    }\n    export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView;\n    export interface ToolRunContext extends ToolExecution {\n        deferContext(context: HookContext): void;\n    }\n    export interface ToolSchema {\n        name: string;\n        description: string;\n        parameters: Record<string, unknown>;\n    }"}],"isError":false},"sourceEventSeqs":[11],"surfaceOp":"append"}
 {"type":"step/end","seq":13,"time":1784449176732,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":14,"time":1784449176733,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":15,"time":1783951000015,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
diff --git a/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/stdout.expected.jsonl
index f5b9745710..48d6fe11a3 100644
--- a/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/cordis-inspect-jsdoc/stdout.expected.jsonl
@@ -1,9 +1,9 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Inspect the exact tools service","updatedAt":"{{updatedAt}}"}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"inspect-tools-api","title":"Inspect cordis runtime: api: tools","kind":"read","status":"in_progress"}}}
-{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"inspect-tools-api","status":"completed","content":[{"type":"content","content":{"type":"text","text":"## api\n- tools — Tool registry and execution pipeline.\n    /**\n     * Register globally or in the calling agent scope. Scoped tools shadow\n     * globals; duplicates within one layer and the reserved `run_code` name fail.\n     * @param definition - the tool schema, execution, and optional presentation functions.\n     * @returns the exact disposer that unregisters the tool.\n     */\n    register(definition: ToolDefinition): () => void\n    /**\n     * Restrict global tools for the calling agent scope. Empty filters, unknown\n     * names, scope-local names, and reserved transport names fail. Restrictions\n     * intersect; scoped registrations remain visible.\n     * @param filter - global-surface mask: `allow` (keep only) and/or `deny` (remove).\n     * @returns the exact disposer that lifts this restriction.\n     */\n    restrict(filter: ToolRestriction): () => void\n    /**\n     * Register a monotonic guard after the extensible `tools/pre-execute`\n     * waterfall. A plain-context guard applies globally; one registered through\n     * `agent.ctx` applies only to that agent. Any matching guard may deny by\n     * returning a reason, while no guard can force-allow a call another guard\n     * denied. The exact effect disposer is returned for ordered ownership and\n     * HMR cleanup.\n     * @param guard - synchronous check; a returned string denies the execution.\n     * @returns the exact disposer that unregisters the guard.\n     */\n    guard(guard: ToolGuard): () => void\n    /**\n     * Look up a tool as one scope sees it (scoped\n     * shadows global; a restricted-away global reads as absent). Presenters pass\n     * the calling agent so the rendered card matches the definition that\n     * actually executed.\n     * @param name - the tool name as registered.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns the definition the scope resolves, or undefined when none is visible.\n     */\n    get(name: string, scope?: ScopeKey): ToolDefinition | undefined\n    /**\n     * Project visible definitions onto the allowlisted model-facing schema fields,\n     * excluding execution and presentation callbacks.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns one deep-cloned schema per visible tool.\n     */\n    schemas(scope?: ScopeKey): ToolSchema[]\n    /**\n     * Classify a pending call through the caller's visible tool definition. Only\n     * an exact `true` is parallel; unknown, hidden, undeclared, invalid, or\n     * throwing classifiers are exclusive.\n     * @param exec - call name, parsed arguments, and optional agent scope.\n     * @returns the fail-closed scheduling mode.\n     */\n    executionMode(exec: ToolExecutionInput): ToolExecutionMode\n    /**\n     * Execute through pre-policy, guards, around-dispatch, post-policy, and final\n     * notification. Tool and listener failures resolve as materialized error\n     * results; an invisible tool reports `UNKNOWN_TOOL`. The returned outcome is\n     * the same lossless, frozen snapshot final observers receive. Cancellation\n     * arriving after entry and before final result materialization skips a\n     * not-yet-started body with `ABORTED_BEFORE_DISPATCH` or replaces a\n     * successful started outcome with `ABORTED`; already-started work is still\n     * drained and may retain a tool-owned structured error.\n     * @param exec - the typed same-process call input. The registry assigns its\n     *   correlation token before policy begins.\n     * @returns the materialized final result.\n     */\n    async execute(exec: ToolExecutionInput): Promise<ToolExecutionResult>\ntype shapes (referenced by the signatures above — read these before assuming a field is a string):\n    export interface Agent {\n        readonly id: SessionId;\n        readonly options: AgentOptions;\n        readonly session: Session;\n        readonly status: AgentStatus;\n        readonly ctx: Context;\n        send(content: ContentBlock[], options?: SendOptions): void;\n        steer(content: ContentBlock[], options?: SendOptions): void;\n        inject(content: ContentBlock[], options?: InjectOptions): void;\n        cancel(cause?: AgentCancelCause): void;\n        whenIdle(): Promise<void>;\n    }\n    export type AgentCancelCause = {\n        readonly kind: 'user';\n    } | {\n        readonly kind: 'parent';\n    };\n    export interface AgentOptions {\n        provider?: string;\n        model?: string;\n    }\n    export type AgentStatus = 'idle' | 'running' | 'disposed';\n    export type Branded<B extends string> = string & {\n        readonly [BRAND]: B;\n    };\n    export type CallId = Branded<'CallId'>;\n    export interface DiffCallView {\n        card: 'diff';\n        title: string;\n        diffs: FileDiff[];\n        locations?: FileLocation[];\n    }\n    export interface DiffResultView {\n        card: 'diff';\n        title?: string;\n        diffs: FileDiff[];\n    }\n    export interface FileDiff {\n        path: string;\n        oldText: string | null;\n        newText: string;\n    }\n    export interface FileLocation {\n        path: string;\n        line?: number;\n    }\n    export interface GenericCallView {\n        card: 'generic';\n        title: string;\n        kind?: ToolCallKind;\n        rawInput?: unknown;\n        content?: ContentBlock[];\n        locations?: FileLocation[];\n    }\n    export interface GenericResultView {\n        card: 'generic';\n        title?: string;\n        content?: ContentBlock[];\n    }\n    export interface HookContext {\n        content: ContentBlock[];\n        source: MessageSource;\n        meta?: JsonValue;\n    }\n    export interface InjectOptions extends Omit<SendOptions, 'contexts'> {\n        meta?: JsonValue;\n    }\n    export type JsonValue = null | boolean | number | string | JsonValue[] | {\n        [key: string]: JsonValue;\n    };\n    export type MessageSource = MessageSourceMap[keyof MessageSourceMap];\n    export interface MessageSourceMap {\n        user: {\n            kind: 'user';\n        };\n        plugin: {\n            kind: 'plugin';\n            plugin: string;\n        };\n    }\n    export type ScopeKey = object;\n    export interface SendOptions {\n        source?: MessageSource;\n        contexts?: HookContext[];\n    }\n    export type SessionId = Branded<'SessionId'>;\n    export interface TerminalCallView {\n        card: 'terminal';\n        title: string;\n        description?: string;\n        cwd?: string;\n    }\n    export interface TerminalResultView {\n        card: 'terminal';\n        title?: string;\n        output?: string;\n        exitCode?: number;\n        signal?: string;\n    }\n    export type ToolCallKind = 'read' | 'edit' | 'delete' | 'move' | 'search' | 'execute' | 'fetch' | 'other';\n    export type ToolCallView = GenericCallView | TerminalCallView | DiffCallView;\n    export interface ToolDefinition extends ToolSchema {\n        execute(args: unknown, exec: ToolRunContext): Promise<ToolExecuteReturn>;\n        timeoutMs?: number;\n        isConcurrencySafe?(args: unknown): boolean;\n        presentCall?(args: unknown): ToolCallView | undefined;\n        presentResult?(args: unknown, result: ToolResult): ToolResultView | undefined;\n    }\n    export interface ToolErrorInfo {\n        name: string;\n        code: string;\n    }\n    export type ToolExecuteReturn = ContentBlock[] | {\n        content: ContentBlock[];\n        meta?: unknown;\n    };\n    export interface ToolExecution extends ToolExecutionInput {\n        readonly token: ToolExecutionToken;\n    }\n    export interface ToolExecutionInput {\n        readonly callId: CallId;\n        readonly name: string;\n        readonly arguments: unknown;\n        readonly agent?: Agent;\n        readonly parent?: ToolExecutionToken;\n        readonly signal: AbortSignal;\n    }\n    export type ToolExecutionMode = {\n        kind: 'parallel';\n    } | {\n        kind: 'exclusive';\n    };\n    export interface ToolExecutionResult {\n        content: ContentBlock[];\n        isError: boolean;\n        error?: ToolErrorInfo;\n        additionalContexts?: HookContext[];\n        meta?: unknown;\n    }\n    export type ToolExecutionToken = symbol & {\n        readonly [toolExecutionTokenBrand]: true;\n    };\n    export type ToolGuard = (execution: Readonly<ToolExecution>) => string | undefined;\n    export interface ToolRestriction {\n        readonly allow?: readonly string[];\n        readonly deny?: readonly string[];\n    }\n    export interface ToolResult {\n        content: ContentBlock[];\n        isError: boolean;\n        meta?: unknown;\n    }\n    export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView;\n    export interface ToolRunContext extends ToolExecution {\n        deferContext(context: HookContext): void;\n    }\n    export interface ToolSchema {\n        name: string;\n        description: string;\n        parameters: Record<string, unknown>;\n    }"}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"inspect-tools-api","status":"completed","content":[{"type":"content","content":{"type":"text","text":"## api\n- tools — Tool registry and execution pipeline.\n    /**\n     * Register globally or in the calling agent scope. Scoped tools shadow\n     * globals; duplicates within one layer and the reserved `run_code` name fail.\n     * @param definition - the tool schema, execution, and optional presentation functions.\n     * @returns the exact disposer that unregisters the tool.\n     */\n    register(definition: ToolDefinition): () => void\n    /**\n     * Restrict global tools for the calling agent scope. Empty filters, unknown\n     * names, scope-local names, and reserved transport names fail. Restrictions\n     * intersect; scoped registrations remain visible.\n     * @param filter - global-surface mask: `allow` (keep only) and/or `deny` (remove).\n     * @returns the exact disposer that lifts this restriction.\n     */\n    restrict(filter: ToolRestriction): () => void\n    /**\n     * Register a monotonic guard after the extensible `tools/pre-execute`\n     * waterfall. A plain-context guard applies globally; one registered through\n     * `agent.ctx` applies only to that agent. Any matching guard may deny by\n     * returning a reason, while no guard can force-allow a call another guard\n     * denied. The exact effect disposer is returned for ordered ownership and\n     * HMR cleanup.\n     * @param guard - synchronous check; a returned string denies the execution.\n     * @returns the exact disposer that unregisters the guard.\n     */\n    guard(guard: ToolGuard): () => void\n    /**\n     * Look up a tool as one scope sees it (scoped\n     * shadows global; a restricted-away global reads as absent). Presenters pass\n     * the calling agent so the rendered card matches the definition that\n     * actually executed.\n     * @param name - the tool name as registered.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns the definition the scope resolves, or undefined when none is visible.\n     */\n    get(name: string, scope?: ScopeKey): ToolDefinition | undefined\n    /**\n     * Project visible definitions onto the allowlisted model-facing schema fields,\n     * excluding execution and presentation callbacks.\n     * @param scope - the viewing scope (the agent); omitted = the global view.\n     * @returns one deep-cloned schema per visible tool.\n     */\n    schemas(scope?: ScopeKey): ToolSchema[]\n    /**\n     * Classify a pending call through the caller's visible tool definition. Only\n     * an exact `true` is parallel; unknown, hidden, undeclared, invalid, or\n     * throwing classifiers are exclusive.\n     * @param exec - call name, parsed arguments, and optional agent scope.\n     * @returns the fail-closed scheduling mode.\n     */\n    executionMode(exec: ToolExecutionInput): ToolExecutionMode\n    /**\n     * Execute through pre-policy, guards, around-dispatch, post-policy, and final\n     * notification. Tool and listener failures resolve as materialized error\n     * results; an invisible tool reports `UNKNOWN_TOOL`. The returned outcome is\n     * the same lossless, frozen snapshot final observers receive. Cancellation\n     * arriving after entry and before final result materialization skips a\n     * not-yet-started body with `ABORTED_BEFORE_DISPATCH` or replaces a\n     * successful started outcome with `ABORTED`; already-started work is still\n     * drained and may retain a tool-owned structured error.\n     * @param exec - the typed same-process call input. The registry assigns its\n     *   correlation token before policy begins.\n     * @returns the materialized final result.\n     */\n    async execute(exec: ToolExecutionInput): Promise<ToolExecutionResult>\ntype shapes (referenced by the signatures above — read these before assuming a field is a string):\n    export interface Agent {\n        readonly id: SessionId;\n        readonly options: AgentOptions;\n        readonly session: Session;\n        readonly status: AgentStatus;\n        readonly ctx: Context;\n        send(content: ContentBlock[], options?: SendOptions): void;\n        steer(content: ContentBlock[], options?: SendOptions): void;\n        inject(content: ContentBlock[], options?: InjectOptions): void;\n        cancel(cause?: AgentCancelCause): void;\n        whenIdle(): Promise<void>;\n    }\n    export type AgentCancelCause = {\n        readonly kind: 'user';\n    } | {\n        readonly kind: 'parent';\n    };\n    export interface AgentOptions {\n        provider?: string;\n        model?: string;\n    }\n    export type AgentStatus = 'idle' | 'running' | 'disposed';\n    export type Branded<B extends string> = string & {\n        readonly [BRAND]: B;\n    };\n    export type CallId = Branded<'CallId'>;\n    export interface DiffCallView {\n        card: 'diff';\n        title: string;\n        diffs: FileDiff[];\n        locations?: FileLocation[];\n    }\n    export interface DiffResultView {\n        card: 'diff';\n        title?: string;\n        diffs: FileDiff[];\n    }\n    export interface FileDiff {\n        path: string;\n        oldText: string | null;\n        newText: string;\n    }\n    export interface FileLocation {\n        path: string;\n        line?: number;\n    }\n    export interface GenericCallView {\n        card: 'generic';\n        title: string;\n        kind?: ToolCallKind;\n        rawInput?: unknown;\n        content?: ContentBlock[];\n        locations?: FileLocation[];\n    }\n    export interface GenericResultView {\n        card: 'generic';\n        title?: string;\n        content?: ContentBlock[];\n    }\n    export interface HookContext {\n        content: ContentBlock[];\n        source: MessageSource;\n        placement?: 'separate' | 'prompt-prefix';\n        meta?: JsonValue;\n    }\n    export interface InjectOptions extends Omit<SendOptions, 'contexts'> {\n        meta?: JsonValue;\n    }\n    export type JsonValue = null | boolean | number | string | JsonValue[] | {\n        [key: string]: JsonValue;\n    };\n    export type MessageSource = MessageSourceMap[keyof MessageSourceMap];\n    export interface MessageSourceMap {\n        user: {\n            kind: 'user';\n        };\n        plugin: {\n            kind: 'plugin';\n            plugin: string;\n        };\n    }\n    export type ScopeKey = object;\n    export interface SendOptions {\n        source?: MessageSource;\n        contexts?: HookContext[];\n    }\n    export type SessionId = Branded<'SessionId'>;\n    export interface TerminalCallView {\n        card: 'terminal';\n        title: string;\n        description?: string;\n        cwd?: string;\n    }\n    export interface TerminalResultView {\n        card: 'terminal';\n        title?: string;\n        output?: string;\n        exitCode?: number;\n        signal?: string;\n    }\n    export type ToolCallKind = 'read' | 'edit' | 'delete' | 'move' | 'search' | 'execute' | 'fetch' | 'other';\n    export type ToolCallView = GenericCallView | TerminalCallView | DiffCallView;\n    export interface ToolDefinition extends ToolSchema {\n        execute(args: unknown, exec: ToolRunContext): Promise<ToolExecuteReturn>;\n        timeoutMs?: number;\n        isConcurrencySafe?(args: unknown): boolean;\n        presentCall?(args: unknown): ToolCallView | undefined;\n        presentResult?(args: unknown, result: ToolResult): ToolResultView | undefined;\n    }\n    export interface ToolErrorInfo {\n        name: string;\n        code: string;\n    }\n    export type ToolExecuteReturn = ContentBlock[] | {\n        content: ContentBlock[];\n        meta?: unknown;\n    };\n    export interface ToolExecution extends ToolExecutionInput {\n        readonly token: ToolExecutionToken;\n    }\n    export interface ToolExecutionInput {\n        readonly callId: CallId;\n        readonly name: string;\n        readonly arguments: unknown;\n        readonly agent?: Agent;\n        readonly parent?: ToolExecutionToken;\n        readonly signal: AbortSignal;\n    }\n    export type ToolExecutionMode = {\n        kind: 'parallel';\n    } | {\n        kind: 'exclusive';\n    };\n    export interface ToolExecutionResult {\n        content: ContentBlock[];\n        isError: boolean;\n        error?: ToolErrorInfo;\n        additionalContexts?: HookContext[];\n        meta?: unknown;\n    }\n    export type ToolExecutionToken = symbol & {\n        readonly [toolExecutionTokenBrand]: true;\n    };\n    export type ToolGuard = (execution: Readonly<ToolExecution>) => string | undefined;\n    export interface ToolRestriction {\n        readonly allow?: readonly string[];\n        readonly deny?: readonly string[];\n    }\n    export interface ToolResult {\n        content: ContentBlock[];\n        isError: boolean;\n        meta?: unknown;\n    }\n    export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView;\n    export interface ToolRunContext extends ToolExecution {\n        deferContext(context: HookContext): void;\n    }\n    export interface ToolSchema {\n        name: string;\n        description: string;\n        parameters: Record<string, unknown>;\n    }"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"inspect-tools-event","title":"Inspect cordis runtime: events: tools/pre-execute","kind":"read","status":"in_progress"}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"inspect-tools-event","status":"completed","content":[{"type":"content","content":{"type":"text","text":"## events\n- tools/pre-execute [waterfall] — Allow, deny, or ask before dispatch.\n    /**\n     * Allow, deny, or ask before dispatch. `next()` delegates to allow; missing\n     * approval support turns `ask` into denial. Async gates must observe\n     * `exec.signal`; the registry rechecks cancellation after they settle but\n     * never abandons their promise.\n     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent's calls.\n     * @param exec - the pending call (name, parsed arguments, caller agent).\n     * @mode waterfall\n     */\n    'tools/pre-execute'(this: Scoped<ToolRegistry>, exec: ToolExecution, next: () => Promise<PreToolDecision>): Promise<PreToolDecision>\nwaterfall listeners receive a trailing next() and MUST call it to delegate — returning without next() vetoes the chain."}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"CORDIS_INSPECT_JSDOC_OK"}}}}
diff --git a/examples/acp-agent/tests/snapshots/error-finish/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/error-finish/stdout.expected.jsonl
index fcc39c0637..5a30ba236c 100644
--- a/examples/acp-agent/tests/snapshots/error-finish/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/error-finish/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"This prompt triggers a recorded","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/escalation-approved/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/escalation-approved/stdout.expected.jsonl
index 09a23db100..d9b91dc524 100644
--- a/examples/acp-agent/tests/snapshots/escalation-approved/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/escalation-approved/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","id":3,"result":{"configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"workspace-write","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
diff --git a/examples/acp-agent/tests/snapshots/escalation-rejected/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/escalation-rejected/stdout.expected.jsonl
index 0446d46f75..850c9c9187 100644
--- a/examples/acp-agent/tests/snapshots/escalation-rejected/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/escalation-rejected/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","id":3,"result":{"configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"workspace-write","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
diff --git a/examples/acp-agent/tests/snapshots/fs-edit/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-edit/stdout.expected.jsonl
index c6ebeb6a8b..50d3b75ee9 100644
--- a/examples/acp-agent/tests/snapshots/fs-edit/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-edit/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"First use the read tool","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/fs-escalation-approved/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-escalation-approved/stdout.expected.jsonl
index 79c5214374..5c334e4894 100644
--- a/examples/acp-agent/tests/snapshots/fs-escalation-approved/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-escalation-approved/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","id":3,"result":{"configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"workspace-write","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
diff --git a/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.expected.jsonl
index 3d29cd8420..fdd805dc79 100644
--- a/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-policy-reject/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Do NOT use the read","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/fs-read-window/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-read-window/stdout.expected.jsonl
index 5a457efde1..7cdc8cb46b 100644
--- a/examples/acp-agent/tests/snapshots/fs-read-window/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-read-window/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the read tool (NOT","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/fs-read/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-read/stdout.expected.jsonl
index c35d6a3981..d7d65b3886 100644
--- a/examples/acp-agent/tests/snapshots/fs-read/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-read/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the read tool (NOT","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/fs-terminal-card/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-terminal-card/stdout.expected.jsonl
index 9e3690ca5f..91d7e06545 100644
--- a/examples/acp-agent/tests/snapshots/fs-terminal-card/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-terminal-card/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/fs-write-overwrite/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-write-overwrite/stdout.expected.jsonl
index 1562dacc70..3c9db41c59 100644
--- a/examples/acp-agent/tests/snapshots/fs-write-overwrite/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-write-overwrite/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"First use the read tool","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/fs-write/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/fs-write/stdout.expected.jsonl
index a7a81496be..bbf03d9ac9 100644
--- a/examples/acp-agent/tests/snapshots/fs-write/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/fs-write/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the write tool (NOT","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/goal-command-status/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/goal-command-status/stdout.expected.jsonl
index 2ea5b1c29a..3fed6952ad 100644
--- a/examples/acp-agent/tests/snapshots/goal-command-status/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/goal-command-status/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"No goal is currently set.\nUsage: /goal [<objective>|clear|edit <objective>|pause|resume]"}}}}
diff --git a/examples/acp-agent/tests/snapshots/handshake/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/handshake/stdout.expected.jsonl
index e87bb6fec2..bfac238e0b 100644
--- a/examples/acp-agent/tests/snapshots/handshake/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/handshake/stdout.expected.jsonl
@@ -1,3 +1,3 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-cc-posttool-block/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-cc-posttool-block/stdout.expected.jsonl
index aeabe98594..ce0961828e 100644
--- a/examples/acp-agent/tests/snapshots/hook-cc-posttool-block/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-cc-posttool-block/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Call the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-cc-posttool-context/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-cc-posttool-context/stdout.expected.jsonl
index b4bbb1be13..6f17982ce0 100644
--- a/examples/acp-agent/tests/snapshots/hook-cc-posttool-context/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-cc-posttool-context/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-cc-pretool-ask/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-cc-pretool-ask/stdout.expected.jsonl
index 30fba24fbd..65d6006567 100644
--- a/examples/acp-agent/tests/snapshots/hook-cc-pretool-ask/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-cc-pretool-ask/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-cc-pretool-deny/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-cc-pretool-deny/stdout.expected.jsonl
index b25efc21cd..33374f5633 100644
--- a/examples/acp-agent/tests/snapshots/hook-cc-pretool-deny/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-cc-pretool-deny/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-block/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-block/stdout.expected.jsonl
index aa2ff437c6..18c9f4cf13 100644
--- a/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-block/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-block/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","id":3,"result":{"stopReason":"cancelled"}}
diff --git a/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-context/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-context/stdout.expected.jsonl
index 2b5a3f74c8..db328a262c 100644
--- a/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-context/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-cc-promptsubmit-context/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"What is my favorite color?","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-cc-stop-continue/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-cc-stop-continue/stdout.expected.jsonl
index b2d0d6e636..f78707768b 100644
--- a/examples/acp-agent/tests/snapshots/hook-cc-stop-continue/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-cc-stop-continue/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Reply with the single word","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-codex-posttool-block/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-codex-posttool-block/stdout.expected.jsonl
index 64922afe05..fe40439a32 100644
--- a/examples/acp-agent/tests/snapshots/hook-codex-posttool-block/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-codex-posttool-block/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Call the bash tool exactly","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-codex-posttool-context/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-codex-posttool-context/stdout.expected.jsonl
index 686b729e2c..8a0e424b4e 100644
--- a/examples/acp-agent/tests/snapshots/hook-codex-posttool-context/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-codex-posttool-context/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-codex-pretool-block/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-codex-pretool-block/stdout.expected.jsonl
index 602eee1837..bc367bf3e5 100644
--- a/examples/acp-agent/tests/snapshots/hook-codex-pretool-block/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-codex-pretool-block/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-block/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-block/stdout.expected.jsonl
index aa2ff437c6..18c9f4cf13 100644
--- a/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-block/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-block/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","id":3,"result":{"stopReason":"cancelled"}}
diff --git a/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-context/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-context/stdout.expected.jsonl
index 4249a4ba04..6c3b337797 100644
--- a/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-context/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-codex-promptsubmit-context/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"What is my favorite color?","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/hook-codex-stop-continue/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/hook-codex-stop-continue/stdout.expected.jsonl
index bcc1765b96..f50ad2cbc8 100644
--- a/examples/acp-agent/tests/snapshots/hook-codex-stop-continue/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/hook-codex-stop-continue/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Reply with the single word","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/lsp-definition/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/lsp-definition/stdout.expected.jsonl
index a993eff7c2..e237d4c3b4 100644
--- a/examples/acp-agent/tests/snapshots/lsp-definition/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/lsp-definition/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the lsp tool exactly","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/model-switching/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/model-switching/stdout.expected.jsonl
index e7d166b2c9..8c126618e5 100644
--- a/examples/acp-agent/tests/snapshots/model-switching/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/model-switching/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Without using tools, reply with","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/multi-turn/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/multi-turn/stdout.expected.jsonl
index cdc441a921..b9c8a5ed14 100644
--- a/examples/acp-agent/tests/snapshots/multi-turn/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/multi-turn/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Reply with exactly the word:","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/parallel-tool-calls/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/parallel-tool-calls/stdout.expected.jsonl
index 750f1726c8..e35df80d4b 100644
--- a/examples/acp-agent/tests/snapshots/parallel-tool-calls/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/parallel-tool-calls/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the read tool twice","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/permission-switching/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/permission-switching/stdout.expected.jsonl
index d132e3759e..245e18fc58 100644
--- a/examples/acp-agent/tests/snapshots/permission-switching/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/permission-switching/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","id":3,"result":{"configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"workspace-write","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
diff --git a/examples/acp-agent/tests/snapshots/reject-extra-dirs/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/reject-extra-dirs/stdout.expected.jsonl
index 4b864fe7f3..b715cabc47 100644
--- a/examples/acp-agent/tests/snapshots/reject-extra-dirs/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/reject-extra-dirs/stdout.expected.jsonl
@@ -1,2 +1,2 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"error":{"code":-32602,"message":"Invalid params: additionalDirectories is not supported in this MVP"}}
diff --git a/examples/acp-agent/tests/snapshots/repeat-tool-guard/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/repeat-tool-guard/stdout.expected.jsonl
index 247cbecb8b..f6e846798e 100644
--- a/examples/acp-agent/tests/snapshots/repeat-tool-guard/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/repeat-tool-guard/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Write the todo list 'watch","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/skill-load/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/skill-load/stdout.expected.jsonl
index d972b1a032..aadd4f8629 100644
--- a/examples/acp-agent/tests/snapshots/skill-load/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/skill-load/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Load the snapshot-skill skill with","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/subagent-depth-two-rejection/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/subagent-depth-two-rejection/stdout.expected.jsonl
index 7b69668a59..a3d755c026 100644
--- a/examples/acp-agent/tests/snapshots/subagent-depth-two-rejection/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/subagent-depth-two-rejection/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Delegate through two child generations.","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/subagent-fork/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/subagent-fork/stdout.expected.jsonl
index cfff8b76e5..5959682eb2 100644
--- a/examples/acp-agent/tests/snapshots/subagent-fork/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/subagent-fork/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Remember this fact for later:","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/subagent-mixed/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/subagent-mixed/stdout.expected.jsonl
index 13008b8a8e..a70c0cd181 100644
--- a/examples/acp-agent/tests/snapshots/subagent-mixed/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/subagent-mixed/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Remember this fact for later:","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/subagent-multi/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/subagent-multi/stdout.expected.jsonl
index 20cabfa5ef..9fff9978b2 100644
--- a/examples/acp-agent/tests/snapshots/subagent-multi/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/subagent-multi/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the subagent tool TWICE,","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/subagent-spawn/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/subagent-spawn/stdout.expected.jsonl
index 5127a672f0..bd1bae72e4 100644
--- a/examples/acp-agent/tests/snapshots/subagent-spawn/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/subagent-spawn/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the subagent tool exactly","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/text-turn/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/text-turn/stdout.expected.jsonl
index bba9f955f3..bfb6ecd764 100644
--- a/examples/acp-agent/tests/snapshots/text-turn/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/text-turn/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Reply with exactly the word:","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/todo-plan/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/todo-plan/stdout.expected.jsonl
index c4911152ee..ea659a6a2f 100644
--- a/examples/acp-agent/tests/snapshots/todo-plan/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/todo-plan/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the todo_write tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/tool-call-turn/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/tool-call-turn/stdout.expected.jsonl
index b4f15657d6..e423e3ad24 100644
--- a/examples/acp-agent/tests/snapshots/tool-call-turn/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/tool-call-turn/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the bash tool to","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/workflow-run/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/workflow-run/stdout.expected.jsonl
index e3a2ebb673..f04c1ff821 100644
--- a/examples/acp-agent/tests/snapshots/workflow-run/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/workflow-run/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Use the workflow tool exactly","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/workspace-context/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/workspace-context/stdout.expected.jsonl
index 4167839f4c..69bf85a0df 100644
--- a/examples/acp-agent/tests/snapshots/workspace-context/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/workspace-context/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"Read nested/task.txt with the read","updatedAt":"{{updatedAt}}"}}}
diff --git a/examples/acp-agent/tests/snapshots/workspace-edit/stdout.expected.jsonl b/examples/acp-agent/tests/snapshots/workspace-edit/stdout.expected.jsonl
index 16aba07874..7c99e12375 100644
--- a/examples/acp-agent/tests/snapshots/workspace-edit/stdout.expected.jsonl
+++ b/examples/acp-agent/tests/snapshots/workspace-edit/stdout.expected.jsonl
@@ -1,4 +1,4 @@
-{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"sessionCapabilities":{"list":{}},"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"available_commands_update","availableCommands":[{"name":"goal","description":"set or view the goal for a long-running task","input":{"hint":"[<objective>|clear|edit <objective>|pause|resume]"}}]}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"session_info_update","title":"A file named greeting.txt in","updatedAt":"{{updatedAt}}"}}}
diff --git a/packages/context/session-reference/README.md b/packages/context/session-reference/README.md
index cc4504f6a4..b3a4b2013d 100644
--- a/packages/context/session-reference/README.md
+++ b/packages/context/session-reference/README.md
@@ -1,6 +1,6 @@
 # `@deepseek-ai/dsh-session-reference`
 
-`ctx.sessionReferences` prepares bounded, read-only snapshots of other DeepSeek Harness sessions as durable `context/message` input. It consumes `ctx.sessionQuery` and the backend-independent compact checkpoint marker; SQLite FTS is not required. The standard TUI and ACP demo bundles mount it, while other hosts may call the service directly.
+`ctx.sessionReferences` prepares bounded, read-only snapshots of other sessions as prompt-prefix context. It consumes `ctx.sessionQuery` and the backend-independent compact checkpoint marker; SQLite FTS is not required. The standard TUI and ACP demo bundles mount it, while other hosts may call the service directly.
 
 ## Public API
 
@@ -10,9 +10,9 @@
 
 ## Snapshot semantics
 
-Preparation calls `ctx.sessionQuery.readSurface()` once per distinct source and never rereads it after enqueue. It projects only direct-user `user/message`, direct-user `steering/message`, assistant text, and `user/message` checkpoints carrying the canonical `dsh-compact` source marker from the folded current surface. Shadowed pre-compaction events, tools, reasoning, context, plugin-generated user messages other than marked compact checkpoints, and unfinished assistant chunks are excluded. A compacted source therefore contributes its latest checkpoint plus retained later conversation, not restored shadowed text.
+Preparation calls `ctx.sessionQuery.readSurface()` once per distinct source and never rereads it after enqueue. It projects only direct-user `user/message`, direct-user `steering/message`, assistant text, and `user/message` checkpoints carrying the canonical `dsh-compact` source marker from the folded current surface. For a source prompt that already contains baked prefix context, projection reads only its model-hidden display content, preventing recursive snapshot propagation. Shadowed pre-compaction events, tools, reasoning, context, plugin-generated user messages other than marked compact checkpoints, and unfinished assistant chunks are excluded. A compacted source therefore contributes its latest checkpoint plus retained later conversation, not restored shadowed text.
 
-The context source is `{ kind: 'plugin', plugin: 'session-reference' }`. Its metadata records version `1`, source ids and labels, capture seqs, compact presence, retained/omitted message counts, omitted UTF-8 bytes, and truncation state. The target session persists that exact context through the ordinary `context/message` event; later source mutation, compaction, or deletion cannot change target replay.
+The context source is `{ kind: 'plugin', plugin: 'session-reference' }` with `placement: 'prompt-prefix'`. Its metadata records version `1`, source ids and labels, capture seqs, compact presence, retained/omitted message counts, omitted UTF-8 bytes, and truncation state. AgentLoop writes the snapshot, `## My request:` delimiter, and effective prompt into one `user/message` or `steering/message`; the same event's model-hidden envelope retains the direct prompt and metadata for TUI/ACP replay. Later source mutation, compaction, or deletion cannot change target replay.
 
 ## Configuration
 
@@ -30,7 +30,7 @@ Retention applies `maxReferenceBytes` independently to each source, keeps compac
 
 #### What the model sees
 
-The model sees the current message's readable `@label` plus one same-level user-context message headed `## Referenced sessions`. The context states that its JSON is untrusted, read-only background and forbids following instructions, permission claims, or tool requests unless the current user repeats them. Labels, cwd values, ids, and conversation text are serialized as JSON inside `<referenced-sessions>` tags; every data `<` is emitted as the lossless JSON escape `\u003c`, so source text cannot spell a framing tag.
+The model sees one user-role message in this order: the `## Referenced sessions` untrusted snapshot, the `## My request:` delimiter, then the current message with its readable `@label`. The warning forbids following instructions, permission claims, or tool requests from the snapshot unless the current user repeats them. Labels, cwd values, ids, and conversation text are serialized as JSON inside `<referenced-sessions>` tags; every data `<` is emitted as the lossless JSON escape `\u003c`, so source text cannot spell a framing tag.
 
 #### Token effect
 
@@ -38,7 +38,7 @@ Each referenced message adds the fixed warning plus up to three serialized snaps
 
 #### KV Cache effect
 
-Snapshot context is append-only at the target message boundary and preserves earlier cacheable history. Different references or source capture contents change the new suffix only; later target compaction may invalidate reuse from its replacement boundary.
+The combined snapshot and request are append-only at the target message boundary and preserve earlier cacheable history. Different references or source capture contents change the new suffix only; later target compaction may invalidate reuse from its replacement boundary.
 
 ## Known Limitations and Deferred Work
 
diff --git a/packages/context/session-reference/src/index.ts b/packages/context/session-reference/src/index.ts
index 4dbe00f267..93e5173005 100644
--- a/packages/context/session-reference/src/index.ts
+++ b/packages/context/session-reference/src/index.ts
@@ -195,6 +195,7 @@ export class SessionReferenceService extends Service {
     const context: HookContext = {
       source: { kind: 'plugin', plugin: 'session-reference' },
       content: [{ type: 'text', text: prompt }],
+      placement: 'prompt-prefix',
       meta,
     }
     return { content: acceptedContent, contexts: [context] }
diff --git a/packages/context/session-reference/src/projection.ts b/packages/context/session-reference/src/projection.ts
index 5e6d7a02dd..bbb2a2c739 100644
--- a/packages/context/session-reference/src/projection.ts
+++ b/packages/context/session-reference/src/projection.ts
@@ -1,6 +1,7 @@
 /** Current-surface projection and byte-bounded rendering. */
 
 import { isCompactCheckpointSource } from '@deepseek-ai/dsh-compact'
+import { displayPromptContent } from '@deepseek-ai/dsh-session'
 import type { SessionSurfaceSnapshot } from '@deepseek-ai/dsh-session-query'
 import { assertNever } from '@deepseek-ai/dsh-llm'
 import { TextRetainer } from '@deepseek-ai/dsh-retention'
@@ -40,13 +41,13 @@ function projectSessionConversation(snapshot: SessionSurfaceSnapshot): Projected
       case 'user/message': {
         const checkpoint = isCompactCheckpointSource(event.data.source)
         if (!checkpoint && event.data.source.kind !== 'user') break
-        const text = textContent(event.data.content)
+        const text = textContent(displayPromptContent(event.data))
         if (text !== '') conversation.push({ role: 'user', text, checkpoint, originalText: text, omittedBytes: 0 })
         break
       }
       case 'steering/message': {
         if (event.data.source.kind !== 'user') break
-        const text = textContent(event.data.content)
+        const text = textContent(displayPromptContent(event.data))
         if (text !== '') conversation.push({ role: 'user', text, checkpoint: false, originalText: text, omittedBytes: 0 })
         break
       }
diff --git a/packages/context/session-reference/tests/session-reference.spec.ts b/packages/context/session-reference/tests/session-reference.spec.ts
index fc4d0f2136..bb21cfab05 100644
--- a/packages/context/session-reference/tests/session-reference.spec.ts
+++ b/packages/context/session-reference/tests/session-reference.spec.ts
@@ -228,6 +228,7 @@ describe('session reference discovery and preparation', () => {
     const context = prepared.contexts[0]
     if (context?.content[0]?.type !== 'text') throw new Error('expected text context')
     expect(context.source).toEqual({ kind: 'plugin', plugin: 'session-reference' })
+    expect(context.placement).toBe('prompt-prefix')
     expect(context.content[0].text).toContain('untrusted, read-only snapshot')
     expect(promptData(context.content[0].text)).toEqual([{
       sessionId: 'source',
@@ -261,6 +262,36 @@ describe('session reference discovery and preparation', () => {
     expect(context.content[0].text).not.toContain('later source mutation')
   })
 
+  it('projects only the direct prompt when a source message contains baked prefix context', async () => {
+    const ctx = await harness()
+    const target = ctx.sessions.create(SessionId('target'))
+    const source = ctx.sessions.create(SessionId('source'))
+    source.append('user/message', {
+      content: [
+        { type: 'text', text: 'nested referenced snapshot must not propagate' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'direct source question' },
+      ],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'direct source question' }],
+        prefixContexts: [{ source: { kind: 'plugin', plugin: 'session-reference' } }],
+      },
+    }, { surfaceOp: 'append' })
+
+    const prepared = await ctx.sessionReferences.prepare(
+      fakeAgent(target),
+      [{ type: 'text', text: 'inspect source' }],
+      [{ sessionId: source.id }],
+    )
+    const context = prepared.contexts[0]
+    if (context?.content[0]?.type !== 'text') throw new Error('expected text context')
+    expect(promptData(context.content[0].text)).toMatchObject([{
+      conversation: [{ role: 'user', text: 'direct source question' }],
+    }])
+    expect(context.content[0].text).not.toContain('nested referenced snapshot must not propagate')
+  })
+
   it('keeps source text inside tag-safe JSON framing without changing its value', async () => {
     const ctx = await harness()
     const target = ctx.sessions.create(SessionId('target'))
@@ -447,14 +478,19 @@ describe('session reference discovery and preparation', () => {
       [{ type: 'text', text: 'use @source' }],
       [{ sessionId: source.id }],
     )
-    target.append(
-      'user/message',
-      { content: prepared.content, source: { kind: 'user' } },
-      { surfaceOp: 'append' },
-    )
-    for (const context of prepared.contexts) {
-      target.append('context/message', context, { surfaceOp: 'append' })
-    }
+    const context = prepared.contexts[0]
+    if (context === undefined) throw new Error('expected prepared context')
+    target.append('user/message', {
+      content: [...context.content, { type: 'text', text: '\n\n## My request:\n' }, ...prepared.content],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: prepared.content,
+        prefixContexts: [{
+          source: context.source,
+          ...context.meta === undefined ? {} : { meta: context.meta },
+        }],
+      },
+    }, { surfaceOp: 'append' })
     const before = target.deriveMessages()
 
     const later = source.append(
@@ -480,6 +516,7 @@ describe('session reference discovery and preparation', () => {
     expect(ctx.sessions.get(source.id)).toBeUndefined()
     expect(target.deriveMessages()).toEqual(before)
     expect(JSON.stringify(before)).toContain('durable referenced fact')
+    expect(JSON.stringify(before)).toContain('## My request:')
     expect(JSON.stringify(before)).not.toContain('later source mutation')
     expect(new Session(SessionId('replayed-target'), target.events).deriveMessages()).toEqual(before)
   })
diff --git a/packages/cordis/tool-cordis/src/api-catalog.ts b/packages/cordis/tool-cordis/src/api-catalog.ts
index 12896afb11..8c1b16c989 100644
--- a/packages/cordis/tool-cordis/src/api-catalog.ts
+++ b/packages/cordis/tool-cordis/src/api-catalog.ts
@@ -1392,7 +1392,7 @@ export const TYPE_API: readonly TypeApiEntry[] = [
   },
   {
     name: 'HookContext',
-    declaration: 'export interface HookContext {\n    content: ContentBlock[];\n    source: MessageSource;\n    meta?: JsonValue;\n}',
+    declaration: 'export interface HookContext {\n    content: ContentBlock[];\n    source: MessageSource;\n    placement?: \'separate\' | \'prompt-prefix\';\n    meta?: JsonValue;\n}',
   },
   {
     name: 'InjectOptions',
@@ -1466,6 +1466,18 @@ export const TYPE_API: readonly TypeApiEntry[] = [
     name: 'PromptAssembly',
     declaration: 'export interface PromptAssembly {\n    sections: AssembledSection[];\n    tools: ToolSchema[];\n    variables: Record<string, string | undefined>;\n}',
   },
+  {
+    name: 'PromptMessageData',
+    declaration: 'export interface PromptMessageData {\n    content: ContentBlock[];\n    source: MessageSource;\n    envelope?: PromptMessageEnvelope;\n}',
+  },
+  {
+    name: 'PromptMessageEnvelope',
+    declaration: 'export interface PromptMessageEnvelope {\n    displayContent: ContentBlock[];\n    prefixContexts: PromptPrefixContext[];\n}',
+  },
+  {
+    name: 'PromptPrefixContext',
+    declaration: 'export interface PromptPrefixContext {\n    source: MessageSource;\n    meta?: JsonValue;\n}',
+  },
   {
     name: 'PromptSection',
     declaration: 'export interface PromptSection {\n    readonly name: string;\n    readonly order: number;\n    readonly text: string | ((context: AssembleContext) => string);\n}',
@@ -1520,7 +1532,7 @@ export const TYPE_API: readonly TypeApiEntry[] = [
   },
   {
     name: 'SessionEventMap',
-    declaration: 'export interface SessionEventMap {\n    \'turn/start\': {\n        turn: number;\n        trigger: TurnTrigger;\n    };\n    \'turn/end\': {\n        turn: number;\n        reason: TurnEndReason;\n    };\n    \'step/start\': {\n        turn: number;\n        step: number;\n    };\n    \'step/end\': {\n        turn: number;\n        step: number;\n    };\n    \'user/message\': {\n        content: ContentBlock[];\n        source: MessageSource;\n    };\n    \'prompt/blocked\': {\n        content: ContentBlock[];\n        source: MessageSource;\n        reason: string;\n    };\n    \'context/message\': {\n        content: ContentBlock[];\n        source: MessageSource;\n        meta?: JsonValue;\n    };\n    \'assistant/chunk\': {\n        turn: number;\n        step: number;\n        chunk: StreamChunk;\n    };\n    \'assistant/message\': {\n        turn: number;\n        step: number;\n        content: ContentBlock[];\n        provenance: AssistantProvenance;\n        usage?: TokenUsage;\n    };\n    \'tool/call\': {\n        turn: number;\n        step: number;\n        callId: CallId;\n        name: string;\n        arguments: string;\n    };\n    \'tool/result\': {\n        turn: number;\n        step: number;\n        callId: CallId;\n        content: ContentBlock[];\n        isError: boolean;\n        error?: {\n            name: string;\n            code: string;\n        };\n        meta?: unknown;\n    };\n    \'steering/message\': {\n        turn: number;\n        content: ContentBlock[];\n        source: MessageSource;\n    };\n    \'todo/write\': {\n         /* …truncated — full shape in source */',
+    declaration: 'export interface SessionEventMap {\n    \'turn/start\': {\n        turn: number;\n        trigger: TurnTrigger;\n    };\n    \'turn/end\': {\n        turn: number;\n        reason: TurnEndReason;\n    };\n    \'step/start\': {\n        turn: number;\n        step: number;\n    };\n    \'step/end\': {\n        turn: number;\n        step: number;\n    };\n    \'user/message\': PromptMessageData;\n    \'prompt/blocked\': {\n        content: ContentBlock[];\n        source: MessageSource;\n        reason: string;\n    };\n    \'context/message\': {\n        content: ContentBlock[];\n        source: MessageSource;\n        meta?: JsonValue;\n    };\n    \'assistant/chunk\': {\n        turn: number;\n        step: number;\n        chunk: StreamChunk;\n    };\n    \'assistant/message\': {\n        turn: number;\n        step: number;\n        content: ContentBlock[];\n        provenance: AssistantProvenance;\n        usage?: TokenUsage;\n    };\n    \'tool/call\': {\n        turn: number;\n        step: number;\n        callId: CallId;\n        name: string;\n        arguments: string;\n    };\n    \'tool/result\': {\n        turn: number;\n        step: number;\n        callId: CallId;\n        content: ContentBlock[];\n        isError: boolean;\n        error?: {\n            name: string;\n            code: string;\n        };\n        meta?: unknown;\n    };\n    \'steering/message\': PromptMessageData & {\n        turn: number;\n    };\n    \'todo/write\': {\n        todos: TodoItem[];\n    };\n    \'request/header\': {\n        header: EpochHeader;\n        reason: Req /* …truncated — full shape in source */',
   },
   {
     name: 'SessionEventReadRequest',
@@ -1786,6 +1798,10 @@ export const TYPE_API: readonly TypeApiEntry[] = [
     name: 'TerminalResultView',
     declaration: 'export interface TerminalResultView {\n    card: \'terminal\';\n    title?: string;\n    output?: string;\n    exitCode?: number;\n    signal?: string;\n}',
   },
+  {
+    name: 'TodoItem',
+    declaration: 'export interface TodoItem {\n    content: string;\n    status: \'pending\' | \'in_progress\' | \'completed\';\n}',
+  },
   {
     name: 'TokenMeasurement',
     declaration: 'export interface TokenMeasurement {\n    readonly logRevision: number;\n    readonly baseline: TokenMeasurementBaseline;\n    readonly surfaceDeltaTokens: number;\n    readonly totalTokens: number;\n    readonly surfaceTokens: number;\n    readonly nodes: readonly TokenSurfaceNode[];\n}',
diff --git a/packages/core/agent-loop/README.md b/packages/core/agent-loop/README.md
index 1d8cc4d7f0..1b89f288a8 100644
--- a/packages/core/agent-loop/README.md
+++ b/packages/core/agent-loop/README.md
@@ -52,7 +52,7 @@ Configured agents start automatically. A model call requires both `provider` and
 
 The concrete `Agent` class, its `Inbox`, `runLoop`, and instance-bound publication/start controls are package-internal. The package root exports only the plugin/service/config contract, and the package exports map exposes no `./src/*` escape hatch; lifecycle owners create agents through `ctx.agents` rather than naming, constructing, or starting driver internals. One prepared session can be claimed by only one concrete driver, and everything observable happens through session events and the `agent/*` event taxonomy.
 
-Each concrete `send()` materializes content, resolved source, and attached contexts once as a detached, deeply frozen lossless-JSON FIFO item. If claimed, it is the sole ordinary message in its turn; its contexts are the prompt waterfall's default additional contexts and therefore append only after admission. The waterfall's returned allow is authoritative, so a listener wrapping `next()` preserves downstream `content` and `additionalContexts` unless it intentionally replaces them. A successor waits for the preceding ordinary turn's checkpoint to settle, while cancellation, disposal, a prompt block, or a pre-start failure may drop its contexts with the message. Running `steer()` enters the same record shape in the steering FIFO without dispatching `agent/prompt-submit`: an open turn records the steering message followed by its contexts at the next steering checkpoint before a request or continuation decision, but policy can still stop before another step; steering left after turn close and its checkpoint becomes later queued input with contexts intact unless terminal turn policy, cancellation, or disposal discards it. Open-turn `inject()` uses the same accepted-value boundary but defers in a FIFO while the current step executes assistant tool calls; successful batches place it after all results, and interrupted batches drain it before turn close. Malformed data throws before enqueue or append.
+Each concrete `send()` materializes content, resolved source, and attached contexts once as a detached, deeply frozen lossless-JSON FIFO item. If claimed, it is the sole ordinary message in its turn; its contexts are the prompt waterfall's default additional contexts and therefore materialize only after admission. Absent or `separate` placement appends an independent `context/message`; `prompt-prefix` placement bakes the context, the stable `## My request:` delimiter, and effective request into one `user/message`, whose model-hidden envelope retains display content and context descriptors. The waterfall's returned allow is authoritative, so a listener wrapping `next()` preserves downstream `content` and `additionalContexts` unless it intentionally replaces them. A successor waits for the preceding ordinary turn's checkpoint to settle, while cancellation, disposal, a prompt block, or a pre-start failure may drop its contexts with the message. Running `steer()` enters the same record shape in the steering FIFO without dispatching `agent/prompt-submit`; its next checkpoint applies the same separate-or-prefix placement to `steering/message`, while policy can still stop before another step. Steering left after turn close and its checkpoint becomes later queued input with contexts intact unless terminal turn policy, cancellation, or disposal discards it. Open-turn `inject()` uses the same accepted-value boundary but defers in a FIFO while the current step executes assistant tool calls; successful batches place it after all results, and interrupted batches drain it before turn close. Malformed data throws before enqueue or append.
 
 ### Loop lifecycle (`loop.ts`)
 
diff --git a/packages/core/agent-loop/src/loop.ts b/packages/core/agent-loop/src/loop.ts
index 4eccb95294..1cfd913b77 100644
--- a/packages/core/agent-loop/src/loop.ts
+++ b/packages/core/agent-loop/src/loop.ts
@@ -12,7 +12,7 @@ import { BlockAssembler, HarnessError, LlmError, assertNever, deepFreeze, errorC
 import { agentEvents, agentInterruptReasonOf, assembleContextFor } from '@deepseek-ai/dsh-agent'
 import type { AgentEventDispatch, ContinuationDecision, HookContext, PromptDecision, RequestError, RequestErrorDecision } from '@deepseek-ai/dsh-agent'
 import { canonicalHeader } from '@deepseek-ai/dsh-session'
-import type { Session, TurnEndReason, TurnTrigger } from '@deepseek-ai/dsh-session'
+import type { PromptMessageData, Session, TurnEndReason, TurnTrigger } from '@deepseek-ai/dsh-session'
 import { createTransmissionLog, recordRequestHeader } from './request-log.ts'
 import type { TransmissionLog } from './request-log.ts'
 import { renderPrompt } from '@deepseek-ai/dsh-system-prompt'
@@ -92,6 +92,45 @@ function stepFinishReason(finish: FinishReason): TurnEndReason | undefined {
 /** Internal control-flow sentinel; durable classification comes only from the turn signal. */
 const TURN_INTERRUPTED = new Error('turn interrupted')
 
+const PROMPT_PREFIX_REQUEST_DELIMITER: ContentBlock = {
+  type: 'text',
+  text: '\n\n## My request:\n',
+}
+
+interface PreparedPromptMessage {
+  data: PromptMessageData
+  separateContexts: HookContext[]
+}
+
+/** Bake declared prefix contexts into one reconstructable prompt message. */
+function preparePromptMessage(
+  content: ContentBlock[],
+  source: PromptMessageData['source'],
+  contexts: readonly HookContext[],
+): PreparedPromptMessage {
+  const prefixContexts = contexts.filter(context => context.placement === 'prompt-prefix')
+  const separateContexts = contexts.filter(context => context.placement !== 'prompt-prefix')
+  if (prefixContexts.length === 0) return { data: { content, source }, separateContexts }
+  return {
+    data: {
+      content: [
+        ...prefixContexts.flatMap(context => context.content),
+        PROMPT_PREFIX_REQUEST_DELIMITER,
+        ...content,
+      ],
+      source,
+      envelope: {
+        displayContent: content,
+        prefixContexts: prefixContexts.map(context => ({
+          source: context.source,
+          ...context.meta === undefined ? {} : { meta: context.meta },
+        })),
+      },
+    },
+    separateContexts,
+  }
+}
+
 /** Stop at an explicit cooperative boundary without stringifying the runtime reason. */
 function interruptionCheckpoint(signal: AbortSignal): void {
   if (signal.aborted) throw TURN_INTERRUPTED
@@ -240,9 +279,14 @@ async function runTurn(
   const drainSteering = (): boolean => {
     const messages = handle.inbox.drainSteering()
     for (const message of messages) {
-      session.append('steering/message', { turn, content: message.content, source: message.source }, { surfaceOp: 'append' })
-      for (const context of message.contexts) {
-        session.append('context/message', context, { surfaceOp: 'append' })
+      const prepared = preparePromptMessage(message.content, message.source, message.contexts)
+      session.append('steering/message', { turn, ...prepared.data }, { surfaceOp: 'append' })
+      for (const context of prepared.separateContexts) {
+        session.append('context/message', {
+          content: context.content,
+          source: context.source,
+          ...context.meta === undefined ? {} : { meta: context.meta },
+        }, { surfaceOp: 'append' })
       }
     }
     return messages.length > 0
@@ -316,11 +360,12 @@ async function runTurn(
     } else {
       // `allow.content` REPLACES the prompt bytes (a rewrite); absent keeps them.
       const content = promptDecision.content ?? message.content
-      session.append('user/message', { content, source: message.source }, { surfaceOp: 'append' })
-      // Every `allow.additionalContexts` entry is a separate context/message the
-      // next request also sees. The turn is open, so inject() appends each one
-      // into THIS turn without flattening provenance or metadata.
-      for (const context of promptDecision.additionalContexts ?? []) {
+      const prepared = preparePromptMessage(content, message.source, promptDecision.additionalContexts ?? [])
+      session.append('user/message', prepared.data, { surfaceOp: 'append' })
+      // Separate contexts still enter THIS turn through inject(). Prefix
+      // contexts are already baked into the user/message with their durable
+      // display envelope, so appending them again would duplicate model input.
+      for (const context of prepared.separateContexts) {
         agent.inject(context.content, {
           source: context.source,
           ...context.meta !== undefined ? { meta: context.meta } : {},
diff --git a/packages/core/agent-loop/tests/contract-regressions.spec.ts b/packages/core/agent-loop/tests/contract-regressions.spec.ts
index 0a44fc144c..3a9ca87d68 100644
--- a/packages/core/agent-loop/tests/contract-regressions.spec.ts
+++ b/packages/core/agent-loop/tests/contract-regressions.spec.ts
@@ -875,24 +875,51 @@ describe('adapter registration, routing, and accepted-input ownership', () => {
     expect(agent.status).toBe('running')
     const content = [{ type: 'text' as const, text: 'accepted-steer' }]
     const source = { kind: 'plugin' as const, plugin: 'accepted-source' }
-    const contexts: HookContext[] = [{
-      content: [{ type: 'text', text: 'accepted-steering-context' }],
-      source: { kind: 'plugin', plugin: 'steering-context' },
-    }]
+    const contexts: HookContext[] = [
+      {
+        content: [{ type: 'text', text: 'accepted-steering-prefix' }],
+        source: { kind: 'plugin', plugin: 'steering-prefix' },
+        placement: 'prompt-prefix',
+      },
+      {
+        content: [{ type: 'text', text: 'accepted-steering-context' }],
+        source: { kind: 'plugin', plugin: 'steering-context' },
+        meta: { kind: 'separate-card' },
+      },
+      {
+        content: [{ type: 'text', text: 'accepted-steering-context-without-meta' }],
+        source: { kind: 'plugin', plugin: 'steering-context-without-meta' },
+      },
+    ]
     agent.steer(content, { source, contexts })
     content[0]!.text = 'caller-mutated-steer'
     source.plugin = 'caller-mutated-source'
-    contexts[0]!.content[0] = { type: 'text', text: 'caller-mutated-steering-context' }
+    contexts[0]!.content[0] = { type: 'text', text: 'caller-mutated-steering-prefix' }
+    contexts[0]!.placement = 'separate'
+    contexts[1]!.content[0] = { type: 'text', text: 'caller-mutated-steering-context' }
+    contexts[2]!.content[0] = { type: 'text', text: 'caller-mutated-steering-context-without-meta' }
     const idle = waitForIdle(ctx, agent)
     release.resolve(undefined)
     await idle
 
     expect(notifiedContent).toEqual([{ type: 'text', text: 'accepted-steer' }])
     expect(notifiedSource).toEqual({ kind: 'plugin', plugin: 'accepted-source' })
-    expect(notifiedContexts).toEqual([{
-      content: [{ type: 'text', text: 'accepted-steering-context' }],
-      source: { kind: 'plugin', plugin: 'steering-context' },
-    }])
+    expect(notifiedContexts).toEqual([
+      {
+        content: [{ type: 'text', text: 'accepted-steering-prefix' }],
+        source: { kind: 'plugin', plugin: 'steering-prefix' },
+        placement: 'prompt-prefix',
+      },
+      {
+        content: [{ type: 'text', text: 'accepted-steering-context' }],
+        source: { kind: 'plugin', plugin: 'steering-context' },
+        meta: { kind: 'separate-card' },
+      },
+      {
+        content: [{ type: 'text', text: 'accepted-steering-context-without-meta' }],
+        source: { kind: 'plugin', plugin: 'steering-context-without-meta' },
+      },
+    ])
     expect(Object.isFrozen(notifiedContent)).toBe(true)
     expect(Object.isFrozen(notifiedContent?.[0])).toBe(true)
     expect(Object.isFrozen(notifiedSource)).toBe(true)
@@ -900,14 +927,28 @@ describe('adapter registration, routing, and accepted-input ownership', () => {
     const recorded = agent.session.events.flatMap(event => event.type === 'steering/message' ? [event.data] : [])
     expect(recorded).toContainEqual({
       turn: 1,
-      content: [{ type: 'text', text: 'accepted-steer' }],
+      content: [
+        { type: 'text', text: 'accepted-steering-prefix' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'accepted-steer' },
+      ],
       source: { kind: 'plugin', plugin: 'accepted-source' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'accepted-steer' }],
+        prefixContexts: [{
+          source: { kind: 'plugin', plugin: 'steering-prefix' },
+        }],
+      },
     })
     const request = JSON.stringify(adapter.requests[1]!.messages)
     expect(request).toContain('accepted-steer')
+    expect(request).toContain('accepted-steering-prefix')
     expect(request).toContain('accepted-steering-context')
+    expect(request).toContain('accepted-steering-context-without-meta')
     expect(request).not.toContain('caller-mutated-steer')
+    expect(request).not.toContain('caller-mutated-steering-prefix')
     expect(request).not.toContain('caller-mutated-steering-context')
+    expect(request).not.toContain('caller-mutated-steering-context-without-meta')
 
     const steeringIndex = agent.session.events.findIndex(event => event.type === 'steering/message')
     const contextIndex = agent.session.events.findIndex(event => event.type === 'context/message'
diff --git a/packages/core/agent-loop/tests/interception.spec.ts b/packages/core/agent-loop/tests/interception.spec.ts
index a00694d4bb..42a2808170 100644
--- a/packages/core/agent-loop/tests/interception.spec.ts
+++ b/packages/core/agent-loop/tests/interception.spec.ts
@@ -117,6 +117,55 @@ describe('agent/prompt-submit', () => {
     expect(sent).toContain('extra ctx')
   })
 
+  it('bakes prompt-prefix contexts and a request delimiter into one durable user message', async () => {
+    const adapter = new MockAdapter([textResponse('ok')])
+    const ctx = await harness(adapter)
+    const agent = ctx.agentLoop.create(SessionId('prefixed'), { provider: 'mock', model: 'mock' })
+
+    ctx.on('agent/prompt-submit', async (_agent, _content, _source, _signal, next): Promise<PromptDecision> => {
+      const downstream = await next()
+      return downstream.kind === 'block'
+        ? downstream
+        : { ...downstream, content: [{ type: 'text', text: 'rewritten request' }] }
+    })
+    agent.send([{ type: 'text', text: 'original request' }], {
+      contexts: [{
+        content: [{ type: 'text', text: 'untrusted prefix' }],
+        source: { kind: 'plugin', plugin: 'prefix' },
+        placement: 'prompt-prefix',
+        meta: { kind: 'prefix-card' },
+      }],
+    })
+    await waitForIdle(ctx, agent)
+
+    const log = events(agent)
+    const user = log.find(event => event.type === 'user/message')
+    expect(user?.type === 'user/message' && user.data).toEqual({
+      content: [
+        { type: 'text', text: 'untrusted prefix' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'rewritten request' },
+      ],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'rewritten request' }],
+        prefixContexts: [{
+          source: { kind: 'plugin', plugin: 'prefix' },
+          meta: { kind: 'prefix-card' },
+        }],
+      },
+    })
+    expect(log.some(event => event.type === 'context/message')).toBe(false)
+    expect(adapter.requests[0]?.messages.at(-1)).toEqual({
+      role: 'user',
+      content: [
+        { type: 'text', text: 'untrusted prefix' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'rewritten request' },
+      ],
+    })
+  })
+
   it('runs pre-step after prompt rewrites and injected context become durable', async () => {
     const adapter = new MockAdapter([textResponse('ok')])
     const ctx = await harness(adapter)
diff --git a/packages/core/agent/README.md b/packages/core/agent/README.md
index e1a82d22bc..b040d8cbdc 100644
--- a/packages/core/agent/README.md
+++ b/packages/core/agent/README.md
@@ -48,7 +48,7 @@ The lifecycle edges have two important local caveats. `agent/created` runs after
 
 Most interception points are cooperative waterfalls returning seam-specific decisions. Turn-scoped asynchronous seams receive one explicit `AbortSignal`, with `signal` immediately before a waterfall's final `next`; listeners may cooperate but must not retain it as authority over another turn. The signal remains authoritative through terminal policy and is retired immediately before `turn/end` publication, so terminal observers and the following durability flush cannot cancel completed turn work. `agent/pre-step` and `agent/post-step` are serial checkpoints around a step's durable work, while `agent/request-error` is the failed-model-request recovery waterfall: it receives the exact error, normalized failure facts, immutable prior-retried facts, and signal after the failed step closes; a retry opens a new numbered step. `agent/turn-stop` is the terminal serial fold: it runs after ordinary continuation and steering folding, and a returned stop remains in force through turn close and flush so later steering cannot create an extra step or turn. Ordinary queued prompts remain intact. Effective broad cancellation first emits the observe-only `agent/cancel-requested` with its resolved typed cause, then clears queues and aborts; notification failures are contained and cannot veto the stop. The [explicit-cancellation decision](../../../.agents/notes/implemented/architecture/2026-07-16-explicit-turn-cancellation.md) owns signal lifetime; the [agent-scope runtime-design Agent Note](../../../.agents/notes/implemented/architecture/2026-07-12-agent-scope-runtime-design.md#three-execution-boundaries-are-deliberately-one-way) owns scoped dispatch and terminal settlement.
 
-`PromptDecision.additionalContexts` is an array so every injected context keeps its own source and metadata. `SendOptions.contexts` binds the same shape to one queued message before prompt interception: the default allow decision carries it forward, while a blocked prompt records no context. A listener that wraps a downstream allow preserves its `content` and `additionalContexts` unless it intentionally replaces either field; the returned allow is authoritative. A `ContinuationDecision` reason is narrower: it becomes a `steering/message`, not a `context/message`, and therefore carries only content and source.
+`PromptDecision.additionalContexts` is an array so every context keeps its own source, metadata, and placement. `SendOptions.contexts` binds the same shape to one queued message before prompt interception: the default allow decision carries it forward, while a blocked prompt records no context. Absent or `separate` placement writes an independent `context/message`; `prompt-prefix` writes the context, `## My request:` delimiter, and effective prompt into one `user/message` or `steering/message`, whose model-hidden envelope retains the direct prompt and context descriptors for human replay. A listener that wraps a downstream allow preserves its `content` and `additionalContexts` unless it intentionally replaces either field; the returned allow is authoritative. A `ContinuationDecision` reason is narrower: it becomes a `steering/message` without attached context metadata.
 
 Turn and step boundaries and the model token stream are durable `session/event` facts rather than mirrored `agent/*` notifications. Consumers read `turn/*`, `step/*`, and `assistant/chunk` from the session feed; tool policy and outcome observation belong to the complete pipeline documented by [`dsh-tools`](../tools/README.md).
 
@@ -56,8 +56,8 @@ Turn and step boundaries and the model token stream are durable `session/event`
 
 The handle every plugin programs against:
 
-- `agent.send(content, options?)` — queue one independent FIFO item. If claimed, that item becomes the sole ordinary message in its turn; a claimed FIFO successor waits for that turn's checkpoint to settle. Broad cancellation, disposal, or a pre-start failure may instead drop it without a turn. Omitting `options.source` attests direct human input as `{ kind: 'user' }` and may authorize policy consumers, so plugins, schedulers, and other non-human producers provide their own source. Content, resolved source, and `options.contexts` become one detached, deeply frozen lossless-JSON record before `agent/queued` and enqueue; invalid data throws synchronously, and caller or notification-listener in-place mutation cannot change the log or model input. The contexts become individual `context/message` events after the accepted user message, unless `agent/prompt-submit` blocks or replaces the default additional-context decision. The [one-send-one-turn Agent Note](../../../.agents/notes/implemented/simplification/2026-07-17-one-send-one-turn.md) owns the turn rationale.
-- `agent.steer(content, options?)` — while running, queue steering for the next checkpoint without dispatching `agent/prompt-submit`; when idle, delegate to `send()`. Attached contexts remain in the same frozen record, append immediately after that steering message when drained, survive late-steering conversion to queued input, and disappear with their message on cancellation or terminal discard. Policy can still stop before another step; after turn close and its checkpoint, remaining steering becomes later queued input unless terminal turn policy, cancellation, or disposal discards it.
+- `agent.send(content, options?)` — queue one independent FIFO item. If claimed, that item becomes the sole ordinary message in its turn; a claimed FIFO successor waits for that turn's checkpoint to settle. Broad cancellation, disposal, or a pre-start failure may instead drop it without a turn. Omitting `options.source` attests direct human input as `{ kind: 'user' }` and may authorize policy consumers, so plugins, schedulers, and other non-human producers provide their own source. Content, resolved source, and `options.contexts` become one detached, deeply frozen lossless-JSON record before `agent/queued` and enqueue; invalid data throws synchronously, and caller or notification-listener in-place mutation cannot change the log or model input. After admission, separate contexts become `context/message` events, while prompt-prefix contexts are baked before the effective request in the same `user/message`; a block or replacement of the default additional-context decision can discard them. The [one-send-one-turn Agent Note](../../../.agents/notes/implemented/simplification/2026-07-17-one-send-one-turn.md) owns the turn rationale.
+- `agent.steer(content, options?)` — while running, queue steering for the next checkpoint without dispatching `agent/prompt-submit`; when idle, delegate to `send()`. Attached contexts remain in the same frozen record; separate contexts append immediately after the steering event, while prompt-prefix contexts are baked into that steering event. Both survive late-steering conversion to queued input and disappear with their message on cancellation or terminal discard. Policy can still stop before another step; after turn close and its checkpoint, remaining steering becomes later queued input unless terminal turn policy, cancellation, or disposal discards it.
 - `agent.inject(content, options?)` — accept detached in-session context without running the model; the next request sees its `context/message` with `content` rendered verbatim as a user-role message. `options.meta` persists opaque JSON state without rendering it. While a turn is open it joins that turn, deferring FIFO while the current tool batch executes and draining before turn close if execution is interrupted; while idle it is wrapped in a one-shot `injection` turn and durability checkpoint ([the turn-enclosure invariant](../../../.agents/notes/implemented/architecture/2026-06-15-turn-enclosure-invariant.md)).
 - `agent.cancel(cause?)` — cancel ALL pending work: an omitted cause means `{ kind: 'user' }`; TypeScript restricts callers to the `user | parent` union, and an active holder copies its discriminant into a detached frozen signal reason before aborting. An effective call emits `agent/cancel-requested` with the cause before clearing queued and steering work; observers may synchronize state but cannot veto cancellation. The same-process typed seam adds no runtime validation or compatibility fallback for untyped callers. Repeated active-turn cancellation is first-wins for the signal, and idle cancellation is a safe no-op with no notification. ACP maps to `user`, while in-process parent propagation maps to `parent`. The cause is runtime-only; durable `turn/end` stays coarse `aborted`.
 - `agent.whenIdle()` — resolve once the agent reaches quiescence after settling out of `running` (idle → immediately; disposed → awaits the loop exit). A non-owner's quiescence-observation hook: it observes the work settling WITHOUT tearing the agent down. Teardown is separate — a lifecycle owner stops and unregisters via `AgentHandle.dispose()`, which awaits the loop exit directly.
diff --git a/packages/core/agent/src/types.ts b/packages/core/agent/src/types.ts
index 1565297f93..dc78d76ef5 100644
--- a/packages/core/agent/src/types.ts
+++ b/packages/core/agent/src/types.ts
@@ -57,17 +57,24 @@ export type AgentStatus = 'idle' | 'running' | 'disposed'
 export interface HookContext {
   content: ContentBlock[]
   source: MessageSource
+  /**
+   * Model placement. Absent or `separate` records an independent
+   * `context/message`; `prompt-prefix` prepends this context and a stable
+   * request delimiter to the same user-role message as its attached prompt.
+   */
+  placement?: 'separate' | 'prompt-prefix'
   /** Opaque JSON state retained in the session event but hidden from the model. */
   meta?: JsonValue
 }
 
 /**
- * Prompt interception result. `allow.content` replaces the prompt and each
- * `additionalContexts` entry becomes a separate context message. `block`
- * records a durable `prompt/blocked` and ends the claimed prompt's zero-step
- * turn as rejected. An `allow` returned by a listener is authoritative: a
- * listener wrapping `next()` preserves downstream `content` and
- * `additionalContexts` unless it intentionally replaces them.
+ * Prompt interception result. `allow.content` replaces the prompt. Each
+ * `additionalContexts` entry follows its declared placement: separate context
+ * message by default, or a prefix inside the prompt's user-role message.
+ * `block` records a durable `prompt/blocked` and ends the claimed prompt's
+ * zero-step turn as rejected. An `allow` returned by a listener is
+ * authoritative: a listener wrapping `next()` preserves downstream `content`
+ * and `additionalContexts` unless it intentionally replaces them.
  */
 export type PromptDecision =
   | { kind: 'allow'; content?: ContentBlock[]; additionalContexts?: HookContext[] }
diff --git a/packages/core/session/README.md b/packages/core/session/README.md
index bba2a21e06..e338e05fe9 100644
--- a/packages/core/session/README.md
+++ b/packages/core/session/README.md
@@ -60,7 +60,7 @@ Durable values need one accepted representation, not a check followed by a secon
 
 `request/header` records a full canonical snapshot of the non-history request envelope with reason `initial`, `resume`, or `change`. `foldRequestHeader()` selects the latest snapshot; legacy delta events and the removed `fallback` reason are rejected. `messagePrefix` remains separate from derived history. See the [reconstructable-requests Agent Note](../../../.agents/notes/implemented/architecture/2026-07-05-reconstructable-requests.md).
 
-`context/message` renders its `content` verbatim as a user-role message, and may attach JSON `meta` for replayable plugin state; metadata remains durable but is excluded from `deriveMessages()`.
+`context/message` renders its `content` verbatim as a user-role message, and may attach JSON `meta` for replayable plugin state; metadata remains durable but is excluded from `deriveMessages()`. A `user/message` or `steering/message` with prompt-prefix context keeps the exact combined model bytes in `content` and stores a model-hidden `envelope` containing the direct `displayContent` and prefix context source/metadata descriptors. `displayPromptContent()` selects the human-facing prompt without changing derived history.
 
 ### Session event vocabulary (`types.ts`)
 
@@ -93,7 +93,7 @@ Every `SessionEvent` carries two optional top-level fields (structural metadata)
 
 #### What the model sees
 
-The model receives projections of `user/message`, `assistant/message`, `tool/result`, `context/message`, and `steering/message` surface entries verbatim: each is a user- or assistant-role message carrying its content blocks unchanged. Tool calls live inside assistant messages. Chunks, boundaries, usage, hook records, todo records, and other log-only events add no message.
+The model receives projections of `user/message`, `assistant/message`, `tool/result`, `context/message`, and `steering/message` surface entries verbatim: each is a user- or assistant-role message carrying its content blocks unchanged. A prompt envelope changes only human presentation; its prefix context and request delimiter are already present in the event content. Tool calls live inside assistant messages. Chunks, boundaries, usage, hook records, todo records, and other log-only events add no message.
 
 #### Token effect
 
diff --git a/packages/core/session/src/index.ts b/packages/core/session/src/index.ts
index 0d804ec977..b560408916 100644
--- a/packages/core/session/src/index.ts
+++ b/packages/core/session/src/index.ts
@@ -11,9 +11,9 @@ import { isAbsolute } from 'node:path'
 import { deepFreeze } from '@deepseek-ai/dsh-llm'
 import { scopeOf, scopeTarget } from '@deepseek-ai/dsh-scope'
 import type { Scoped } from '@deepseek-ai/dsh-scope'
-import type { Message } from '@deepseek-ai/dsh-llm'
+import type { ContentBlock, Message } from '@deepseek-ai/dsh-llm'
 import { SESSION_FORMAT_VERSION, SessionId } from './types.ts'
-import type { CreateSessionOptions, EpochHeader, OutOfBandSessionEventType, SessionEvent, SessionEventMap, SessionEventType, SessionHeader, SurfaceIntent, SurfaceEventType, TurnTrigger } from './types.ts'
+import type { CreateSessionOptions, EpochHeader, OutOfBandSessionEventType, PromptMessageData, SessionEvent, SessionEventMap, SessionEventType, SessionHeader, SurfaceIntent, SurfaceEventType, TurnTrigger } from './types.ts'
 import { snapshotJsonValue } from './json.ts'
 import { SurfaceManager } from './surface.ts'
 import type { SessionSurface } from './surface.ts'
@@ -27,6 +27,15 @@ export type { SessionSurface, SurfaceFoldReplacement, SurfaceFoldResult } from '
 export { foldSurface, isSurfaceEvent, isSurfaceEligibleType } from './surface.ts'
 export { canonicalHeader, foldRequestHeader, headerEquals } from './request-header.ts'
 
+/**
+ * Return the human-facing prompt blocks from a durable prompt message.
+ * @param data - ordinary or steering prompt event data.
+ * @returns the effective direct prompt, excluding baked prefix context.
+ */
+export function displayPromptContent(data: PromptMessageData): ContentBlock[] {
+  return data.envelope?.displayContent ?? data.content
+}
+
 /**
  * Find the latest closed message-triggered turn, excluding injection and
  * plugin-owned zero-step turns.
@@ -521,9 +530,11 @@ export class Session {
     // trace/replay data.
 
     switch (event.type) {
-      // Injected context and mid-turn steering project identically to a user
-      // prompt: content verbatim, in user role. context's `source`/`meta` and
-      // steering's `turn` are log-only and do not reach the model. Do NOT
+      // Injected context, ordinary prompts, and mid-turn steering project
+      // identically in user role: the event's model-facing content stays
+      // verbatim. A prompt envelope is model-hidden display metadata; its
+      // prefix bytes are already present in content. context's `source`/`meta`
+      // and steering's `turn` are also log-only. Do NOT
       // re-add per-type framing (e.g. `<context>`/`<steering>`) here: framing is
       // caller-owned — a producer bakes it into `content`, as workspace-context
       // does with `<system-reminder>` — or, if reintroduced, must be driven by
diff --git a/packages/core/session/src/types.ts b/packages/core/session/src/types.ts
index eb8af8ed31..37c174ea12 100644
--- a/packages/core/session/src/types.ts
+++ b/packages/core/session/src/types.ts
@@ -180,6 +180,37 @@ export interface EpochHeader {
  */
 export type RequestHeaderReason = 'initial' | 'resume' | 'change'
 
+/** Durable model-hidden annotation for one context baked into a prompt message. */
+export interface PromptPrefixContext {
+  /** Producer provenance retained for transcript presentation and inspection. */
+  source: MessageSource
+  /** Opaque JSON state retained in the session event but hidden from the model. */
+  meta?: JsonValue
+}
+
+/**
+ * Human-facing view of a prompt whose exact model content includes prefixed
+ * context. `content` on the owning event remains the reconstructable model
+ * input; this envelope prevents transcript, title, and re-reference consumers
+ * from treating the baked context as direct human text.
+ */
+export interface PromptMessageEnvelope {
+  /** Effective user prompt after interception rewrites, without baked context. */
+  displayContent: ContentBlock[]
+  /** Ordered descriptors for contexts already baked into the event content. */
+  prefixContexts: PromptPrefixContext[]
+}
+
+/** Shared payload for ordinary and steering prompt messages. */
+export interface PromptMessageData {
+  /** Exact model-facing blocks, including any baked prompt-prefix contexts. */
+  content: ContentBlock[]
+  /** Producer provenance for the direct prompt. */
+  source: MessageSource
+  /** Present only when prompt-prefix contexts were baked into `content`. */
+  envelope?: PromptMessageEnvelope
+}
+
 /**
  * The merge-extensible, append-only source of truth for an agent interaction.
  * Message history is derived from this log. Every event is lossless JSON and
@@ -206,7 +237,7 @@ export interface SessionEventMap {
   /** Closes step `step` of turn `turn`. */
   'step/end': { turn: number; step: number }
   /** A user-visible prompt (the queued message claimed for this turn). */
-  'user/message': { content: ContentBlock[]; source: MessageSource }
+  'user/message': PromptMessageData
   /**
    * Durable record of a prompt veto and its reason. It is log-only: the blocked
    * prompt never enters the model-visible surface, and its turn runs zero steps.
@@ -254,7 +285,7 @@ export interface SessionEventMap {
    */
   'tool/result': { turn: number; step: number; callId: CallId; content: ContentBlock[]; isError: boolean; error?: { name: string; code: string }; meta?: unknown }
   /** Steering content injected between steps of a running turn. */
-  'steering/message': { turn: number; content: ContentBlock[]; source: MessageSource }
+  'steering/message': PromptMessageData & { turn: number }
   /** Whole-list snapshot; latest write wins on replay. Log-only UI state; never derived history. */
   'todo/write': { todos: TodoItem[] }
   /**
diff --git a/packages/core/session/tests/session.spec.ts b/packages/core/session/tests/session.spec.ts
index 45d2df121a..d880153dd3 100644
--- a/packages/core/session/tests/session.spec.ts
+++ b/packages/core/session/tests/session.spec.ts
@@ -2,6 +2,7 @@ import { describe, expect, expectTypeOf, it, vi } from 'vitest'
 import { Context } from 'cordis'
 import { CallId } from '@deepseek-ai/dsh-llm'
 import SessionStore, {
+  displayPromptContent,
   findLastMessageTurnEnd,
   SESSION_FORMAT_VERSION,
   Session,
@@ -135,6 +136,35 @@ describe('Session', () => {
     expect(steeringMessage!.content).toEqual([{ type: 'text', text: 'focus on tests' }])
   })
 
+  it('derives baked prompt context while exposing only the direct prompt for display', () => {
+    const session = new Session(SessionId('prompt-envelope'))
+    const event = session.append('user/message', {
+      content: [
+        { type: 'text', text: 'background' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'question' },
+      ],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'question' }],
+        prefixContexts: [{ source: { kind: 'plugin', plugin: 'reference' }, meta: { kind: 'card' } }],
+      },
+    }, { surfaceOp: 'append' })
+
+    expect(session.deriveMessages()).toEqual([{
+      role: 'user',
+      content: [
+        { type: 'text', text: 'background' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'question' },
+      ],
+    }])
+    expect(displayPromptContent(event.data)).toEqual([{ type: 'text', text: 'question' }])
+    expect(Object.isFrozen(event.data.envelope?.displayContent)).toBe(true)
+    expect(new Session(SessionId('prompt-envelope-replay'), session.events).deriveMessages())
+      .toEqual(session.deriveMessages())
+  })
+
   it('keeps context meta durable in the event while hiding it from the projection', () => {
     const session = new Session(SessionId('s2-raw'))
     const meta = {
diff --git a/packages/examples/acp-demo/tests/built-bin.e2e.ts b/packages/examples/acp-demo/tests/built-bin.e2e.ts
index fb6662291e..c476a491c2 100644
--- a/packages/examples/acp-demo/tests/built-bin.e2e.ts
+++ b/packages/examples/acp-demo/tests/built-bin.e2e.ts
@@ -18,6 +18,7 @@ import { Readable, Writable } from 'node:stream'
 import { promisify } from 'node:util'
 import { zstdDecompress } from 'node:zlib'
 import { afterEach, describe, expect, it } from 'vitest'
+import { ACP_SESSION_REFERENCE_META_KEY } from '@deepseek-ai/dsh-acp'
 
 /**
  * Published-entry smoke: run `lib/bin.js` under plain Node in a symlinked external consumer and
@@ -35,7 +36,8 @@ const dshPackages = [
   'core/tools', 'core/agent-loop', 'llm/llm', 'bash/bash',
   'bash/bash-local', 'bash/tool-bash', 'context/workspace-context', 'support/invariants', 'ui/app-boot',
   'session-persistence/session-persistence',
-  'session-persistence/session-persistence-jsonl', 'ui/acp', 'examples/acp-demo', 'util/paths',
+  'session-persistence/session-persistence-jsonl', 'session-query/session-query',
+  'context/session-reference', 'ui/acp', 'examples/acp-demo', 'util/paths',
 ]
 const vendorPackages = [
   'cordis', 'loader', 'include', 'timer', 'hmr', 'logger-console',
@@ -165,10 +167,30 @@ describe.skipIf(!existsSync(acpBin))('dsh-acp-demo BUILT bin (node lib/bin.js, n
     // regression would exit before answering); loadSession proves the real app
     // mounted, not a collapsed export shape.
     expect(init.agentCapabilities?.loadSession).toBe(true)
-    const { sessionId } = await client.newSession({ cwd: consumer, mcpServers: [] })
+    expect(init.agentCapabilities?.sessionCapabilities?.list).toEqual({})
+    const sessionCwd = consumer
+    const { sessionId } = await client.newSession({ cwd: sessionCwd, mcpServers: [] })
     const result = await client.prompt({ sessionId, prompt: [{ type: 'text', text: 'reply' }] })
     expect(result.stopReason).toBe('end_turn')
-    const sessionsRoot = join(consumer, '.sessions')
+    await expect.poll(async () => {
+      return (await client.listSessions({ cwd: sessionCwd })).sessions.find(candidate => candidate.sessionId === sessionId)
+    }).toMatchObject({
+      sessionId,
+      cwd: sessionCwd,
+      title: 'reply',
+    })
+    const listed = await client.listSessions({ cwd: sessionCwd })
+    const reference = listed.sessions.find(candidate => candidate.sessionId === sessionId)
+      ?._meta?.[ACP_SESSION_REFERENCE_META_KEY]
+    expect(reference).toBeTypeOf('object')
+    expect(reference).not.toBeNull()
+    expect(reference).toHaveProperty('uri')
+    if (typeof reference !== 'object' || reference === null || !('uri' in reference)) {
+      throw new Error('expected session reference metadata')
+    }
+    expect(reference.uri).toBeTypeOf('string')
+    expect(reference.uri).toMatch(/^dsh-session:[A-Za-z0-9_-]+$/u)
+    const sessionsRoot = join(sessionCwd, '.sessions')
     let log: string | undefined
     await expect.poll(async () => {
       log = (await readdir(sessionsRoot, { recursive: true })).find(file => file.endsWith('.jsonl.zstd'))
diff --git a/packages/session-title/session-title/src/index.ts b/packages/session-title/session-title/src/index.ts
index a4a516b68e..4551bd87d2 100644
--- a/packages/session-title/session-title/src/index.ts
+++ b/packages/session-title/session-title/src/index.ts
@@ -14,6 +14,7 @@ import type {
   SessionEvent,
   SessionEventMap,
 } from '@deepseek-ai/dsh-session'
+import { displayPromptContent } from '@deepseek-ai/dsh-session'
 import { fallbackSessionTitle, normalizeSessionTitle } from './normalize.ts'
 
 export { fallbackSessionTitle, normalizeSessionTitle, truncateTitleUtf8 } from './normalize.ts'
@@ -201,8 +202,9 @@ export function collectSessionTitleMessages(
   for (const event of events) {
     if (throughSeq !== undefined && event.seq > throughSeq) break
     if (event.type !== 'user/message' || event.data.source.kind !== 'user') continue
-    const text = event.data.content
-      .filter((block): block is Extract<(typeof event.data.content)[number], { type: 'text' }> => block.type === 'text')
+    const content = displayPromptContent(event.data)
+    const text = content
+      .filter((block): block is Extract<(typeof content)[number], { type: 'text' }> => block.type === 'text')
       .map(block => block.text)
       .join('\n')
     if (normalizeSessionTitle(text, Number.MAX_SAFE_INTEGER).length === 0) continue
diff --git a/packages/session-title/session-title/tests/session-title.spec.ts b/packages/session-title/session-title/tests/session-title.spec.ts
index d33ad791d2..836ed30f3b 100644
--- a/packages/session-title/session-title/tests/session-title.spec.ts
+++ b/packages/session-title/session-title/tests/session-title.spec.ts
@@ -72,6 +72,33 @@ describe('SessionTitleService', () => {
     expect(session.surface.nodes).toEqual([message.seq])
   })
 
+  it('derives a fallback title from the direct prompt instead of baked prefix context', async () => {
+    const ctx = new Context()
+    await ctx.plugin(SessionStore)
+    await ctx.plugin(SessionTitleService, CONFIG)
+    const session = ctx.sessions.create(SessionId('prefixed-title'))
+    session.append('turn/start', {
+      turn: 1,
+      trigger: { kind: 'message', source: { kind: 'user' } },
+    })
+    session.append('user/message', {
+      content: [
+        { type: 'text', text: 'referenced snapshot title must stay hidden' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'Explain this referenced session' },
+      ],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'Explain this referenced session' }],
+        prefixContexts: [{ source: { kind: 'plugin', plugin: 'session-reference' } }],
+      },
+    }, { surfaceOp: 'append' })
+
+    await settleTitles()
+
+    expect(ctx.sessionTitle.get(session)?.title).toBe('Explain this referenced session')
+  })
+
   it('waits through synthetic, empty, and non-text messages, then keeps the first fallback', async () => {
     const ctx = new Context()
     await ctx.plugin(SessionStore)
diff --git a/packages/ui/acp/README.md b/packages/ui/acp/README.md
index 70d93d3954..3a8576df74 100644
--- a/packages/ui/acp/README.md
+++ b/packages/ui/acp/README.md
@@ -8,7 +8,7 @@ It is a **client-driver / UI plugin**, the structured analogue of the terminal `
 
 `apply(ctx, config)` — wires an `AgentSideConnection` (from `@agentclientprotocol/sdk`) to `process.stdin`/`process.stdout` and implements the ACP `Agent` method surface.
 
-The plugin injects `agents`, [`commands`](../commands/README.md), `sessionPersistence`, `tools`, `userInteraction`, `llm`, and `systemPrompt`, never the concrete loop. Persistence backs `session/load`; the command registry backs slash discovery and direct dispatch; the LLM catalog backs model selection; prompt assembly keeps model variables aligned with routing; tool definitions own presentation; user interaction maps agent questions to ACP forms.
+The plugin injects `agents`, [`commands`](../commands/README.md), `sessionPersistence`, `sessionQuery`, `tools`, `userInteraction`, `llm`, and `systemPrompt`, never the concrete loop. Persistence backs `session/load`; live-preferred session queries back `session/list`; the command registry backs slash discovery and direct dispatch; the LLM catalog backs model selection; prompt assembly keeps model variables aligned with routing; tool definitions own presentation; user interaction maps agent questions to ACP forms.
 
 ### Config
 
@@ -25,9 +25,10 @@ The `initialize` handshake reports a fixed server identity (`agentInfo: { name:
 
 | ACP method | Harness seam | Notes |
 |---|---|---|
-| `initialize` | static | negotiate `protocolVersion`; advertise baseline prompt capabilities (`text`, plus `resource_link` rendered as text) and `loadSession: true` |
+| `initialize` | static | negotiate `protocolVersion`; advertise baseline prompt capabilities (`text`, plus `resource_link` rendered as text), `loadSession: true`, and `sessionCapabilities.list` |
 | `session/new` | `ctx.agents.create({ sessionId, meta:{cwd} })` | creates a new session/agent; N concurrent sessions are allowed, keyed by id; advertises the effective command snapshot; `cwd` must be absolute (it becomes the session's workspace — see Per-session cwd); non-empty `additionalDirectories` and `mcpServers` rejected |
 | `session/load` | `ctx.agents.resume(...)` | reserves the id, verifies the persisted cwd, resumes, replays user, assistant, tool, and title events, and re-advertises commands |
+| `session/list` | `ctx.sessionQuery` | returns live-preferred newest-first sessions with absolute cwd and optional folded title; supports exact normalized cwd filtering, returns no cursor, and rejects supplied cursors |
 | `session/prompt` | `ctx.commands.execute()` or `agent.send()` | a flattened prompt beginning with `/` stays in the direct command plane; ordinary prompts support ACP `text` and `resource_link`; `dsh-session:` links and inline mentions are snapshotted through optional `ctx.sessionReferences` before enqueue; unsupported content, unavailable reference capability, failed snapshots, and empty prompts are rejected; one request is in flight per session and settles on the owning turn's end, with an error turn rejecting the RPC |
 | `session/cancel` | command `AbortSignal` or `agent.cancel()` | aborts the exact direct command, or applies the queue-aware agent cancel and settles its prompt `cancelled`; one session never cancels another |
 | `session/update` | `session/event` | streams user replay, assistant text/reasoning, retry/failure attempt markers, tool render intents, and `session_info_update` title revisions |
@@ -57,6 +58,8 @@ ACP updates are append-only, so `llm/retry` emits a visible separator that marks
 
 A log-only `session/title` event maps to ACP `session_info_update` with `title` and the event timestamp as `updatedAt`. The same mapping runs for live events and `session/load` replay, so an asynchronously generated late title and a restored persisted title have one wire representation without entering model history.
 
+`session/list` returns the same latest folded title in standard `SessionInfo.title`. When `ctx.sessionReferences` is mounted, each listed item also carries `_meta["deepseek-harness/sessionReference"].uri`; a title-aware client can render `title ?? sessionId` in its `@` picker and submit that URI as a `resource_link` with the same display name. Sessions without cwd are omitted because ACP requires an absolute `SessionInfo.cwd` and the bridge cannot load them.
+
 ## Per-session cwd
 
 `session/new` records the request's absolute cwd in the session header. Before constructing an agent, `session/load` uses persisted metadata to require an absolute request cwd that matches the stored one. Bash defaults to that workspace; an explicit relative workdir resolves against it, and multiple sessions may use different workspaces. `additionalDirectories` remains unsupported.
@@ -190,7 +193,7 @@ Loading does not rewrite the stored log, but the next request is reconstructed u
 
 - **`additionalDirectories`** — rejected. A session operates in its single `cwd` (see Per-session cwd); widening the tool/filesystem scope to extra roots is a separate sandbox concern, not yet implemented.
 - **Prompt content is `text` + `resource_link` only** — image, audio, and embedded-resource blocks are rejected, as is a non-empty `mcpServers` list at `session/new`.
-- **Session picker UI is client-owned** — the server accepts canonical resource links and inline mentions, but does not add a picker to ACP clients; title/full-text discovery remains future metadata or FTS work.
+- **Session picker UI is client-owned** — `session/list` supplies standard title metadata and, when references are available, a canonical URI extension; an ACP client must consume those fields to add an `@` picker. Title/body search remains future metadata or FTS work.
 - **Terminal cards render completed output** — live incremental streaming and command classification are named follow-ups of [the terminal-rendering Agent Note](../../../.agents/notes/implemented/feature/2026-06-18-acp-terminal-and-tool-rendering.md).
 - **Permission answers are one-shot only** — the bridge offers `allow_once` / `reject_once`; durable `allow_always` grants and their storage/revocation policy remain deferred to the approval seam.
 - **Command output is live-only** — discovery is refreshed after load, but direct command results are not persisted or replayed into a reconnected editor.
diff --git a/packages/ui/acp/acp-feature-support.md b/packages/ui/acp/acp-feature-support.md
index 60c7b19adf..ea730301c3 100644
--- a/packages/ui/acp/acp-feature-support.md
+++ b/packages/ui/acp/acp-feature-support.md
@@ -10,13 +10,13 @@ Legend: ✅ supported · ⚠️ partial / fallback · ❌ not yet · — n/a. Th
 
 ## At a glance
 
-The bridge implements the **core prompt-turn loop** for N concurrent sessions: initialize, session new/load, prompt, cancel, streamed assistant/thought chunks, tool-call rendering (including Zed terminal cards), resumable session replay, slash commands, one-shot permission prompts, per-session model selection, and permission presets. The largest **unbuilt** areas are **MCP passthrough** and **agent plans**, plus the client **filesystem** and **terminal** method families (which the adapters mostly do NOT drive either — see rows 43-49). See [Gap summary](#gap-summary).
+The bridge implements the **core prompt-turn loop** for N concurrent sessions: initialize, session new/load/list, prompt, cancel, streamed assistant/thought chunks, tool-call rendering (including Zed terminal cards), resumable session replay, slash commands, one-shot permission prompts, per-session model selection, and permission presets. The largest **unbuilt** areas are **MCP passthrough** and **agent plans**, plus the client **filesystem** and **terminal** method families (which the adapters mostly do NOT drive either — see rows 43-49). See [Gap summary](#gap-summary).
 
 ## 1. Agent methods (client → agent)
 
 | Method | Stable | Bridge | Claude | Codex | Notes |
 |---|---|---|---|---|---|
-| `initialize` | S | ✅ | ✅ | ✅ | Negotiates `PROTOCOL_VERSION`; advertises `loadSession` + baseline prompt caps. Snapshots the Zed `_meta.terminal_output` client cap. |
+| `initialize` | S | ✅ | ✅ | ✅ | Negotiates `PROTOCOL_VERSION`; advertises `loadSession`, `sessionCapabilities.list`, and baseline prompt caps. Snapshots the Zed `_meta.terminal_output` client cap. |
 | `authenticate` | S | ⚠️ | ✅ | ✅ | No-op stub; the bridge advertises no `authMethods`, so there is nothing to authenticate. |
 | `logout` | S | ❌ | ✅ | ✅ | Gated by `agentCapabilities.auth.logout`; not advertised. |
 | `session/new` | S | ✅ | ✅ | ✅ | Maps to `agents.create`; requires an absolute `cwd` (becomes the session workspace); rejects non-empty `additionalDirectories` / `mcpServers`. |
@@ -28,7 +28,7 @@ The bridge implements the **core prompt-turn loop** for N concurrent sessions: i
 | `session/set_mode` | S | ❌ | ✅ | ✅ | Session modes deliberately skipped: config options are the spec's replacement and modes are slated for removal in ACP v2 (see [§6](#6-session-modes--config-options--models)). |
 | `session/set_config_option` | S | ✅ | ✅ | ✅ | A provider/model select is present for a complete registered target; one `permission` select is added when `ctx.permission` is composed. Every response carries the complete refreshed state. |
 | model selection | S | ✅ | ✅ | ✅ | No distinct stable `session/set_model` — model is the `model`-category `session/set_config_option`. Values preserve the provider/model pair, catalogs come from `ctx.llm`, selection is per session, and `session/load` restores the last requested pair. Codex also supports the legacy `unstable_setSessionModel` ext method. |
-| `session/list` | S | ❌ | ✅ | ✅ | Gated by `sessionCapabilities.list`. The harness HAS `sessionPersistence.list()` (used internally for load-cwd validation) but does not expose it over ACP. |
+| `session/list` | S | ✅ | ✅ | ✅ | Uses live-preferred `ctx.sessionQuery`; returns absolute-cwd sessions newest-first with optional folded title and exact cwd filtering. Pagination is not emitted; supplied cursors are rejected. |
 | `session/delete` | S | ❌ | ✅ | ✅ | Gated by `sessionCapabilities.delete`. |
 | `session/fork` | U | ❌ | ✅ | ❌ | Claude ships `unstable_forkSession`; Codex does not. |
 
@@ -60,7 +60,7 @@ These are capabilities the bridge would *drive* on the editor. The harness runs
 | `promptCapabilities.audio` | S | ❌ | ❌ | ❌ | `audio: false`; neither adapter accepts audio either. |
 | `promptCapabilities.embeddedContext` | S | ❌ | ✅ | ✅ | `embeddedContext: false`; embedded `resource` blocks rejected. |
 | `mcpCapabilities.{http,sse}` | S | ❌ | ✅ | ⚠️ | No MCP passthrough; `mcpServers` is rejected. Claude advertises http+sse, Codex http only. |
-| `sessionCapabilities.*` | S | ❌ | ✅ | ✅ | None advertised (list/delete/resume/close/additionalDirectories/fork all off). |
+| `sessionCapabilities.*` | S | ⚠️ | ✅ | ✅ | `list` is advertised; delete/resume/close/additionalDirectories/fork remain off. |
 | `auth.logout` | S | ❌ | ✅ | ✅ | Not advertised. |
 | `authMethods[]` | S | ⚠️ | ✅ | ✅ | Advertised as empty (no auth required to reach the model). |
 | `agentInfo` (name/version) | S | ✅ | ✅ | ✅ | Fixed literals: `deepseek-harness-acp` / `0.0.1` (not config). |
@@ -88,7 +88,7 @@ These are capabilities the bridge would *drive* on the editor. The harness runs
 | `current_mode_update` | S | ❌ | ✅ | ✅ | No session modes. |
 | `config_option_update` | S | ❌ | ✅ | ✅ | Config options exist (advertised in `session/new`/`session/load`, switched via `session/set_config_option`), but the bridge never pushes agent-initiated changes — an operator default drift is narrated to the MODEL, not echoed to the editor. Future work in the [sandbox Agent Note § Per-session mode switching](../../../.agents/notes/implemented/feature/2026-07-06-sandbox.md). |
 | `usage_update` | S | ❌ | ✅ | ✅ | Token/cost reporting not surfaced (the harness records token usage internally on `assistant/message`). |
-| `session_info_update` | S | ❌ | ⚠️ | ⚠️ | Session title/metadata not pushed. |
+| `session_info_update` | S | ✅ | ⚠️ | ⚠️ | Log-backed title events push title and event time; load replay uses the same mapping. |
 
 ## 5. Tool-call rendering
 
@@ -132,7 +132,7 @@ The bridge rejects unsupported prompt blocks rather than silently dropping them
 | `StopReason` mapping | S | ✅ | `turnEndToStopReason` is total over harness turn-end reasons → `end_turn`/`max_tokens`/`cancelled`. |
 | Multi-session (N per connection) | S | ✅ | Strict per-session demux; concurrent streams never interleave. See the [multi-session Agent Note](../../../.agents/notes/implemented/feature/2026-06-14-acp-multi-session.md). |
 | Disconnect / disposal teardown | S | ✅ | Quiesces every live session on client disconnect or Cordis disposal. |
-| `_meta` extensibility | S | ⚠️ | Consumed (Zed terminal cap) and emitted (terminal `_meta`); no other custom extensions. |
+| `_meta` extensibility | S | ⚠️ | Consumed for the Zed terminal cap and emitted for terminal cards. Listed sessions add `deepseek-harness/sessionReference` with a canonical URI when cross-session references are mounted. |
 | Background-task ownership isolation | — | ✅ | Generic `task_output`/`task_kill` reject tasks whose branded owner `SessionId` belongs to another session. |
 | stdout-is-the-protocol guarantee | S | ✅ | The bridge runs in an example with no stdout logger. |
 
@@ -140,7 +140,7 @@ The bridge rejects unsupported prompt blocks rather than silently dropping them
 
 Ranked by how commonly the reference adapters ship them and how much UX they unlock:
 
-1. **Session lifecycle** — `session/list` + `session/delete` (the persistence layer already lists), then `session/resume` / `session/close`.
+1. **Session lifecycle** — `session/delete`, then `session/resume` / `session/close`.
 2. **Agent plan** (`sessionUpdate: 'plan'`) — surface the loop's plan as structured entries.
 3. **MCP passthrough** (`mcpServers` on `session/new` + `mcpCapabilities`).
 4. **Richer prompt content** — image / embedded `resource` blocks (needs a multimodal model path).
diff --git a/packages/ui/acp/package.json b/packages/ui/acp/package.json
index 060bb43390..a565442b31 100644
--- a/packages/ui/acp/package.json
+++ b/packages/ui/acp/package.json
@@ -42,6 +42,7 @@
     "@deepseek-ai/dsh-sandbox": "^0.0.1",
     "@deepseek-ai/dsh-session": "^0.0.1",
     "@deepseek-ai/dsh-session-reference": "^0.0.1",
+    "@deepseek-ai/dsh-session-query": "^0.0.1",
     "@deepseek-ai/dsh-session-title": "^0.0.1",
     "@deepseek-ai/dsh-session-persistence": "^0.0.1",
     "@deepseek-ai/dsh-system-prompt": "^0.0.1",
diff --git a/packages/ui/acp/src/index.ts b/packages/ui/acp/src/index.ts
index 20461d96e1..bae5c630e1 100644
--- a/packages/ui/acp/src/index.ts
+++ b/packages/ui/acp/src/index.ts
@@ -27,6 +27,8 @@ import {
   type EnumOption,
   type InitializeRequest,
   type InitializeResponse,
+  type ListSessionsRequest,
+  type ListSessionsResponse,
   type LoadSessionRequest,
   type LoadSessionResponse,
   type NewSessionRequest,
@@ -54,8 +56,8 @@ import {
   type AgentLlmTargetRef as LlmTargetRef,
 } from '@deepseek-ai/dsh-agent'
 import type {} from '@deepseek-ai/dsh-commands'
-import type {} from '@deepseek-ai/dsh-session-reference'
-import { SessionId } from '@deepseek-ai/dsh-session'
+import { encodeSessionReferenceUri } from '@deepseek-ai/dsh-session-reference'
+import { displayPromptContent, SessionId } from '@deepseek-ai/dsh-session'
 // Side-effect type import: resolves `ctx.get('permission')` to the service.
 import type {} from '@deepseek-ai/dsh-permission'
 import type { SessionEvent, TodoItem, TurnEndReason } from '@deepseek-ai/dsh-session'
@@ -65,6 +67,9 @@ import type { ToolCallView, ToolRegistry, ToolResultView, TerminalResultView } f
 // Side-effect type import: declaration-merges `ctx.sessionPersistence` onto
 // Context (the bridge injects it and reads `list()` for load cwd validation).
 import type {} from '@deepseek-ai/dsh-session-persistence'
+// Side-effect type import: declaration-merges the exact-read service used by
+// session/list for live-preferred title folding.
+import type {} from '@deepseek-ai/dsh-session-query'
 // Side-effect type import: declaration-merges prompt assembly onto Context and
 // the scoped waterfall used to keep persona variables aligned with requests.
 import type {} from '@deepseek-ai/dsh-system-prompt'
@@ -89,7 +94,10 @@ import {
 
 export const name = 'acp'
 // Interface services back loading, presentation, interaction, and prompt assembly.
-export const inject = ['agents', 'commands', 'sessionPersistence', 'tools', 'userInteraction', 'llm', 'systemPrompt']
+export const inject = ['agents', 'commands', 'sessionPersistence', 'sessionQuery', 'tools', 'userInteraction', 'llm', 'systemPrompt']
+
+/** ACP `SessionInfo._meta` key carrying a ready-to-submit session-reference URI. */
+export const ACP_SESSION_REFERENCE_META_KEY = 'deepseek-harness/sessionReference'
 
 /** Preserve invalid-parameter detail in the SDK wire error message. */
 function invalidParams(detail: string): RequestError {
@@ -694,6 +702,7 @@ export function apply(ctx: Context, config: AcpConfig): void {
           agentInfo: { name: 'deepseek-harness-acp', version: '0.0.1' },
           agentCapabilities: {
             loadSession: true,
+            sessionCapabilities: { list: {} },
             // Baseline prompt blocks only: text plus resource_link rendered as
             // text. No image/audio/embeddedContext, no mcpCapabilities.
             promptCapabilities: { image: false, audio: false, embeddedContext: false },
@@ -708,6 +717,41 @@ export function apply(ctx: Context, config: AcpConfig): void {
         return Promise.resolve()
       },
 
+      async listSessions(params: ListSessionsRequest): Promise<ListSessionsResponse> {
+        assertOpen()
+        if (params.cursor !== undefined && params.cursor !== null) {
+          throw invalidParams('session/list does not paginate; omit cursor')
+        }
+        if (params.cwd !== undefined && params.cwd !== null && !isAbsolute(params.cwd)) {
+          throw invalidParams('session/list cwd must be absolute')
+        }
+        const records = (await ctx.sessionQuery.listSessions()).flatMap((record) => {
+          const cwd = record.header.cwd
+          if (cwd === undefined) return []
+          if (params.cwd !== undefined && params.cwd !== null && !sameWorkspaceCwd(cwd, params.cwd)) return []
+          return [{ record, cwd }]
+        })
+        const titles = await Promise.all(records.map(({ record }) => ctx.sessionQuery.readTitle(record.header.id)))
+        assertOpen()
+        const referencesAvailable = ctx.get('sessionReferences') !== undefined
+        return {
+          sessions: records.map(({ record, cwd }, index) => ({
+            sessionId: record.header.id,
+            cwd,
+            ...titles[index] === undefined ? {} : { title: titles[index].title },
+            ...referencesAvailable
+              ? {
+                _meta: {
+                  [ACP_SESSION_REFERENCE_META_KEY]: {
+                    uri: encodeSessionReferenceUri(record.header.id),
+                  },
+                },
+              }
+              : {},
+          })),
+        }
+      },
+
       async newSession(params: NewSessionRequest): Promise<NewSessionResponse> {
         assertOpen()
         validateWorkspaceParams(params)
@@ -1247,7 +1291,7 @@ export function streamSessionEventUpdate(
       // Replay the user's prompt so a loaded session shows both sides of each
       // turn. Live prompt turns suppress this path to avoid duplicating what
       // the client just sent.
-      for (const block of event.data.content) {
+      for (const block of displayPromptContent(event.data)) {
         const content = harnessBlockToAcpContent(block)
         if (content !== undefined) {
           notify({ sessionId, update: { sessionUpdate: 'user_message_chunk', content } })
diff --git a/packages/ui/acp/tests/bridge.spec.ts b/packages/ui/acp/tests/bridge.spec.ts
index ec14c8a419..4be67bef98 100644
--- a/packages/ui/acp/tests/bridge.spec.ts
+++ b/packages/ui/acp/tests/bridge.spec.ts
@@ -370,17 +370,22 @@ describe('acp bridge', () => {
 
     const target = harness.ctx.agents.get(SessionId(sessionId))!.session
     const user = target.events.find(event => event.type === 'user/message')
-    expect(user?.type === 'user/message' && user.data.content).toEqual([
-      { type: 'text', text: 'use @source-inline and @source-link' },
-    ])
-    const context = target.events.find(event => event.type === 'context/message')
-    expect(context?.type === 'context/message' && context.data.meta).toMatchObject({
-      kind: 'session-reference',
-      references: [{ sessionId: 'source', label: 'source-inline' }],
+    expect(user?.type === 'user/message' && user.data.envelope).toMatchObject({
+      displayContent: [{ type: 'text', text: 'use @source-inline and @source-link' }],
+      prefixContexts: [{
+        source: { kind: 'plugin', plugin: 'session-reference' },
+        meta: {
+          kind: 'session-reference',
+          references: [{ sessionId: 'source', label: 'source-inline' }],
+        },
+      }],
     })
+    expect(target.events.some(event => event.type === 'context/message')).toBe(false)
     const request = JSON.stringify(harness.adapter.requests[0]?.messages)
     expect(request).toContain('untrusted, read-only snapshot')
     expect(request).toContain('source background')
+    expect(request.indexOf('source background')).toBeLessThan(request.indexOf('## My request:'))
+    expect(request.indexOf('## My request:')).toBeLessThan(request.indexOf('use @source-inline and @source-link'))
   })
 
   it('rejects a failed referenced-session read before starting a turn', async () => {
diff --git a/packages/ui/acp/tests/harness.ts b/packages/ui/acp/tests/harness.ts
index c6de8878b1..2cb7ef1cb5 100644
--- a/packages/ui/acp/tests/harness.ts
+++ b/packages/ui/acp/tests/harness.ts
@@ -218,8 +218,8 @@ export async function makeBridgeHarness(options: {
   await ctx.plugin(CommandService)
   await ctx.plugin(AgentLoop, { agents: [] })
   await ctx.plugin(SessionPersistenceJsonl, { root: options.storageDir })
+  await ctx.plugin(SessionQueryService)
   if (options.withSessionReferences) {
-    await ctx.plugin(SessionQueryService)
     await ctx.plugin(SessionReferenceService)
   }
   await ctx.plugin(UserInteractionService)
diff --git a/packages/ui/acp/tests/session-list.spec.ts b/packages/ui/acp/tests/session-list.spec.ts
new file mode 100644
index 0000000000..fe9e554e60
--- /dev/null
+++ b/packages/ui/acp/tests/session-list.spec.ts
@@ -0,0 +1,92 @@
+import { afterEach, beforeEach, describe, expect, it } from 'vitest'
+import { mkdtemp, rm } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { PROTOCOL_VERSION } from '@agentclientprotocol/sdk'
+import { SessionId } from '@deepseek-ai/dsh-session'
+import type {} from '@deepseek-ai/dsh-session-title'
+import { encodeSessionReferenceUri } from '@deepseek-ai/dsh-session-reference'
+import { ACP_SESSION_REFERENCE_META_KEY } from '../src/index.ts'
+import { makeBridgeHarness, type BridgeHarness } from './harness.ts'
+
+describe('acp bridge — session/list', () => {
+  let storageDir: string
+  let harness: BridgeHarness | undefined
+
+  beforeEach(async () => { storageDir = await mkdtemp(join(tmpdir(), 'acp-list-')) })
+  afterEach(async () => {
+    await harness?.dispose()
+    harness = undefined
+    await rm(storageDir, { recursive: true, force: true })
+  })
+
+  it('advertises title-aware listing and reference metadata for loadable sessions', async () => {
+    harness = await makeBridgeHarness({ storageDir, withSessionReferences: true })
+    const initialized = await harness.client.initialize({ protocolVersion: PROTOCOL_VERSION, clientCapabilities: {} })
+    expect(initialized.agentCapabilities?.sessionCapabilities?.list).toEqual({})
+
+    const cwd = process.cwd()
+    const { sessionId } = await harness.client.newSession({ cwd, mcpServers: [] })
+    const session = harness.ctx.agents.get(SessionId(sessionId))!.session
+    await harness.ctx.sessions.appendOutOfBand(session, 'session/title', {
+      title: 'Reference source title',
+      messageSeqs: [],
+      source: { kind: 'fallback' },
+    }, { kind: 'session-title' })
+    harness.ctx.sessions.create(SessionId('untitled'), { meta: { cwd: join(storageDir, 'other') } })
+    harness.ctx.sessions.create(SessionId('missing-cwd'))
+
+    const listed = await harness.client.listSessions({})
+    expect(listed.nextCursor).toBeUndefined()
+    expect(listed.sessions.map(item => item.sessionId)).toEqual(expect.arrayContaining([sessionId, 'untitled']))
+    expect(listed.sessions.map(item => item.sessionId)).not.toContain('missing-cwd')
+    const source = listed.sessions.find(item => item.sessionId === sessionId)
+    expect(source).toMatchObject({ cwd, title: 'Reference source title' })
+    expect(source?._meta?.[ACP_SESSION_REFERENCE_META_KEY]).toEqual({
+      uri: encodeSessionReferenceUri(SessionId(sessionId)),
+    })
+    expect(listed.sessions.find(item => item.sessionId === 'untitled')).not.toHaveProperty('title')
+  })
+
+  it('filters by normalized cwd and omits reference metadata without the optional capability', async () => {
+    harness = await makeBridgeHarness({ storageDir })
+    await harness.client.initialize({ protocolVersion: PROTOCOL_VERSION, clientCapabilities: {} })
+    const firstCwd = join(storageDir, 'first')
+    const secondCwd = join(storageDir, 'second')
+    const first = await harness.client.newSession({ cwd: firstCwd, mcpServers: [] })
+    await harness.client.newSession({ cwd: secondCwd, mcpServers: [] })
+
+    const listed = await harness.client.listSessions({ cursor: null, cwd: firstCwd })
+    expect(listed.sessions).toHaveLength(1)
+    expect(listed.sessions[0]).toMatchObject({ sessionId: first.sessionId, cwd: firstCwd })
+    expect(listed.sessions[0]?._meta).toBeUndefined()
+    await expect(harness.client.listSessions({ cwd: null })).resolves.toHaveProperty('sessions')
+  })
+
+  it('rejects unsupported cursors and relative cwd filters', async () => {
+    harness = await makeBridgeHarness({ storageDir })
+    await harness.client.initialize({ protocolVersion: PROTOCOL_VERSION, clientCapabilities: {} })
+    await expect(harness.client.listSessions({ cursor: 'next' })).rejects.toThrow('session/list does not paginate')
+    await expect(harness.client.listSessions({ cwd: 'relative' })).rejects.toThrow('session/list cwd must be absolute')
+  })
+
+  it('folds titles from persisted sessions in a fresh bridge', async () => {
+    harness = await makeBridgeHarness({ storageDir, withSessionReferences: true })
+    await harness.client.initialize({ protocolVersion: PROTOCOL_VERSION, clientCapabilities: {} })
+    const cwd = process.cwd()
+    const { sessionId } = await harness.client.newSession({ cwd, mcpServers: [] })
+    const session = harness.ctx.agents.get(SessionId(sessionId))!.session
+    await harness.ctx.sessions.appendOutOfBand(session, 'session/title', {
+      title: 'Persisted reference title',
+      messageSeqs: [],
+      source: { kind: 'fallback' },
+    }, { kind: 'session-title' })
+    await harness.dispose()
+
+    harness = await makeBridgeHarness({ storageDir, withSessionReferences: true })
+    await harness.client.initialize({ protocolVersion: PROTOCOL_VERSION, clientCapabilities: {} })
+    await expect(harness.client.listSessions({ cwd })).resolves.toMatchObject({
+      sessions: [{ sessionId, cwd, title: 'Persisted reference title' }],
+    })
+  })
+})
diff --git a/packages/ui/acp/tests/stream-update.spec.ts b/packages/ui/acp/tests/stream-update.spec.ts
index 7908242d43..89cf69f4f2 100644
--- a/packages/ui/acp/tests/stream-update.spec.ts
+++ b/packages/ui/acp/tests/stream-update.spec.ts
@@ -204,6 +204,24 @@ describe('streamSessionEventUpdate', () => {
     expect(updatesFor(evt('user/message', { content: [], source: { kind: 'user' } }))).toEqual([])
   })
 
+  it('replays only the direct prompt from a prefixed user message', () => {
+    expect(updatesFor(evt('user/message', {
+      content: [
+        { type: 'text', text: 'internal prefix' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'visible request' },
+      ],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'visible request' }],
+        prefixContexts: [{ source: { kind: 'plugin', plugin: 'reference' } }],
+      },
+    }))).toEqual([{
+      sessionUpdate: 'user_message_chunk',
+      content: { type: 'text', text: 'visible request' },
+    }])
+  })
+
   it('can suppress user/message chunks for live prompt turns', () => {
     expect(liveUpdatesFor(evt('user/message', {
       content: [{ type: 'text', text: 'hi' }],
diff --git a/packages/ui/acp/tsconfig.json b/packages/ui/acp/tsconfig.json
index f049f4410f..599683735d 100644
--- a/packages/ui/acp/tsconfig.json
+++ b/packages/ui/acp/tsconfig.json
@@ -29,6 +29,9 @@
     {
       "path": "../../context/session-reference"
     },
+    {
+      "path": "../../session-query/session-query"
+    },
     {
       "path": "../../session-title/session-title"
     },
diff --git a/packages/ui/tui/src/index.ts b/packages/ui/tui/src/index.ts
index 08b477cb91..b3692b7686 100644
--- a/packages/ui/tui/src/index.ts
+++ b/packages/ui/tui/src/index.ts
@@ -56,7 +56,7 @@ import type {
   TokenUsage,
 } from '@deepseek-ai/dsh-llm'
 import type {} from '@deepseek-ai/dsh-llm-retry'
-import { SessionId, type Session, type SessionEvent, type TodoItem } from '@deepseek-ai/dsh-session'
+import { displayPromptContent, SessionId, type Session, type SessionEvent, type TodoItem } from '@deepseek-ai/dsh-session'
 import {
   formatSessionReferenceMention,
   parseSessionReferenceText,
@@ -1113,6 +1113,13 @@ function sessionReferenceCard(meta: unknown): string[] | undefined {
   return labels
 }
 
+function promptReferenceCards(event: Extract<SessionEvent, { type: 'user/message' | 'steering/message' }>): string[][] {
+  return event.data.envelope?.prefixContexts.flatMap((context) => {
+    const card = sessionReferenceCard(context.meta)
+    return card === undefined ? [] : [card]
+  }) ?? []
+}
+
 function activeToolCallIds(session: Session, active: ReadonlySet<number>): Set<string> {
   const ids = new Set<string>()
   for (const event of session.events) {
@@ -1372,20 +1379,28 @@ export function createTuiChat(
   const renderEvent = (event: SessionEvent, options: { addHistory: boolean; renderChunks: boolean }): void => {
     switch (event.type) {
       case 'user/message': {
-        const text = displayText(contentText(event.data.content).trim())
+        const text = displayText(contentText(displayPromptContent(event.data)).trim())
         if (text) {
           chat.addChild(new Spacer(1))
           chat.addChild(new UserMessageComponent(text, palette, mdTheme))
           if (options.addHistory) editor.addToHistory(text)
         }
+        for (const references of promptReferenceCards(event)) {
+          chat.addChild(new Spacer(1))
+          chat.addChild(new Text(palette.dim(`Referenced sessions · ${references.map(displayText).join(', ')}`), 1, 0))
+        }
         break
       }
       case 'steering/message': {
-        const text = displayText(contentText(event.data.content).trim())
+        const text = displayText(contentText(displayPromptContent(event.data)).trim())
         if (text) {
           chat.addChild(new Spacer(1))
           chat.addChild(new UserMessageComponent(text, palette, mdTheme, 'Steering'))
         }
+        for (const references of promptReferenceCards(event)) {
+          chat.addChild(new Spacer(1))
+          chat.addChild(new Text(palette.dim(`Referenced sessions · ${references.map(displayText).join(', ')}`), 1, 0))
+        }
         break
       }
       case 'context/message': {
diff --git a/packages/ui/tui/tests/session-reference.snapshot.ts b/packages/ui/tui/tests/session-reference.snapshot.ts
index 8fcf86fa93..4fecad3b86 100644
--- a/packages/ui/tui/tests/session-reference.snapshot.ts
+++ b/packages/ui/tui/tests/session-reference.snapshot.ts
@@ -24,9 +24,14 @@ class SnapshotAdapter extends LlmAdapter {
 
   async * stream(options: GenerateOptions): AsyncIterable<StreamChunk> {
     this.requests.push(options)
+    const prompt = options.messages.at(-1)
+    if (prompt?.role !== 'user' || prompt.content.length !== 3
+      || prompt.content[1]?.type !== 'text' || prompt.content[1].text !== '\n\n## My request:\n') {
+      throw new Error('session reference did not reach the model as one prefixed user message')
+    }
     yield { type: 'block-start', index: 0, blockType: 'text' }
-    yield { type: 'text-delta', index: 0, text: 'Snapshot reference accepted.' }
-    yield { type: 'block-end', index: 0, block: { type: 'text', text: 'Snapshot reference accepted.' } }
+    yield { type: 'text-delta', index: 0, text: 'Combined reference request accepted.' }
+    yield { type: 'block-end', index: 0, block: { type: 'text', text: 'Combined reference request accepted.' } }
     yield { type: 'finish', reason: { kind: 'stop' } }
   }
 }
@@ -108,11 +113,22 @@ describe('TUI session-reference snapshot', () => {
     expect(request).toContain('Recent retained question.')
     expect(request).not.toContain('SHADOWED OLD USER')
     expect(request).not.toContain('SHADOWED OLD ASSISTANT')
-    const context = target.session.events.find(event => event.type === 'context/message')
-    expect(context?.type === 'context/message' && context.data.meta).toMatchObject({
-      kind: 'session-reference',
-      references: [{ sessionId: 'source-session', compacted: true }],
+    const user = target.session.events.find(event => event.type === 'user/message')
+    expect(user?.type === 'user/message' && user.data.envelope).toMatchObject({
+      displayContent: [{ type: 'text', text: 'Use @Source session' }],
+      prefixContexts: [{
+        source: { kind: 'plugin', plugin: 'session-reference' },
+        meta: {
+          kind: 'session-reference',
+          references: [{ sessionId: 'source-session', compacted: true }],
+        },
+      }],
     })
+    expect(user?.type === 'user/message' && user.data.content[1]).toEqual({
+      type: 'text',
+      text: '\n\n## My request:\n',
+    })
+    expect(target.session.events.some(event => event.type === 'context/message')).toBe(false)
 
     const snapshot = await terminal.snapshot({ includeScrollback: true })
     if (REFRESHING) {
diff --git a/packages/ui/tui/tests/snapshots/session-reference.expected.txt b/packages/ui/tui/tests/snapshots/session-reference.expected.txt
index e936b920ee..cb2de02e5e 100644
--- a/packages/ui/tui/tests/snapshots/session-reference.expected.txt
+++ b/packages/ui/tui/tests/snapshots/session-reference.expected.txt
@@ -36,7 +36,7 @@ buffer
 12| <blank>
 13| " Assistant                                                                                      "
   style 1-9 fg=bright-magenta bold
-14| " Snapshot reference accepted.                                                                   "
+14| " Combined reference request accepted.                                                           "
 15| "────────────────────────────────────────────────────────────────────────────────────────────────"
   style 0-95 dim
 16| "                                                                                                "
diff --git a/packages/ui/tui/tests/tui.spec.ts b/packages/ui/tui/tests/tui.spec.ts
index 895e7cd8ef..5a91249d34 100644
--- a/packages/ui/tui/tests/tui.spec.ts
+++ b/packages/ui/tui/tests/tui.spec.ts
@@ -750,6 +750,56 @@ describe('pi-tui chat lifecycle and transcript', () => {
     expect(result.terminal.output).toContain('Session reference failed')
     expect(result.terminal.output).toContain('keep @[')
 
+    result.session.append('user/message', {
+      content: [
+        { type: 'text', text: 'hidden baked snapshot payload' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'visible referenced question' },
+      ],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'visible referenced question' }],
+        prefixContexts: [{
+          source: { kind: 'plugin', plugin: 'session-reference' },
+          meta: {
+            kind: 'session-reference',
+            references: [{ sessionId: 'prefixed', label: 'Prefixed source' }],
+          },
+        }],
+      },
+    }, { surfaceOp: 'append' })
+    await tick()
+    expect(result.terminal.output).toContain('visible referenced question')
+    expect(result.terminal.output).toContain('Referenced sessions · Prefixed source (prefixed)')
+    expect(result.terminal.output).not.toContain('hidden baked snapshot payload')
+
+    result.session.append('steering/message', {
+      turn: 1,
+      content: [
+        { type: 'text', text: 'hidden non-reference prefix' },
+        { type: 'text', text: '\n\n## My request:\n' },
+        { type: 'text', text: 'visible steering prompt' },
+      ],
+      source: { kind: 'user' },
+      envelope: {
+        displayContent: [{ type: 'text', text: 'visible steering prompt' }],
+        prefixContexts: [
+          { source: { kind: 'plugin', plugin: 'other' }, meta: { kind: 'other' } },
+          {
+            source: { kind: 'plugin', plugin: 'session-reference' },
+            meta: {
+              kind: 'session-reference',
+              references: [{ sessionId: 'steering-source', label: 'Steering source' }],
+            },
+          },
+        ],
+      },
+    }, { surfaceOp: 'append' })
+    await tick()
+    expect(result.terminal.output).toContain('visible steering prompt')
+    expect(result.terminal.output).toContain('Referenced sessions · Steering source (steering-source)')
+    expect(result.terminal.output).not.toContain('hidden non-reference prefix')
+
     result.session.append('context/message', {
       content: [{ type: 'text', text: 'secret full snapshot payload' }],
       source: { kind: 'plugin', plugin: 'session-reference' },
diff --git a/scripts/type-equiv.manifest.json b/scripts/type-equiv.manifest.json
index 21cedfeef6..4b6b0aa91b 100644
--- a/scripts/type-equiv.manifest.json
+++ b/scripts/type-equiv.manifest.json
@@ -64,6 +64,7 @@
     { "doc": "docs/core-data-structures/token-meter.md", "symbol": "TokenMeasurement", "source": "packages/llm/token-meter/src/types.ts" },
     { "doc": "docs/core-data-structures/token-meter.md", "symbol": "TokenSurfaceNode", "source": "packages/llm/token-meter/src/types.ts" },
 
+    { "doc": "docs/core-data-structures/session.md", "symbol": "PromptMessageData", "source": "packages/core/session/src/types.ts" },
     { "doc": "docs/core-data-structures/session.md", "symbol": "SessionEventMap", "source": "packages/core/session/src/types.ts" },
     { "doc": "docs/core-data-structures/session.md", "symbol": "OutOfBandSessionEventMap", "source": "packages/core/session/src/types.ts" },
     { "doc": "docs/core-data-structures/session.md", "symbol": "EpochHeader", "source": "packages/core/session/src/types.ts" },