Merge commit 'refs/codex-unblock/2026-07-23/base-511' into HEAD

2026-07-23 10:14:06 +08:00
parent f728a1b8a2 690c53dc03
commit 08cc034128
563 changed files with 22576 additions and 3319 deletions
--- a/docs/agent-lifecycle.md
+++ b/docs/agent-lifecycle.md
@@ -23,7 +23,7 @@ sequenceDiagram
  Driver-->>SDK: <code>agent/status</code> running
  Driver->>Session: <code>turn/start</code>
  Driver->>Hooks: <code>agent/prompt-submit</code> waterfall
-  Hooks-->>Driver: allow, block, or add context
+  Hooks-->>Driver: authoritative allow, block, or add context
  Driver->>Session: <code>user/message</code> or rejected <code>turn/end</code>
  Driver->>Prompt: <code>system-prompt/assemble</code> waterfall
  Driver-->>Driver: <code>agent/pre-step</code> serial checkpoint
@@ -51,7 +51,7 @@ sequenceDiagram
      Driver->>Session: <code>tool/result</code>
    end
  end
-  Driver->>Session: post-tool context and steering
+  Driver->>Session: post-tool context and steering (no prompt-submit)
  Driver->>Hooks: <code>agent/post-step</code> serial checkpoint
  Driver->>Session: <code>step/end</code>
  Driver->>Hooks: <code>agent/turn-continuation</code> waterfall
@@ -66,6 +66,8 @@ The `assistant/message` edge records every successful provider call, including c

 `dsh-compact-basic` uses `agent/post-step` for pressure after those durable facts and `agent/request-error` only for canonical context overflow. Once either trigger qualifies, optional tool-result pruning runs before summary selection. Recovery works between the closed failed step and a fresh retry step, and returns retry only when pruning or summarization advances the surface replacement generation; otherwise the original request error remains authoritative.

+The returned `agent/prompt-submit` allow is authoritative; listeners wrapping `next()` preserve downstream content and additional contexts unless replacement is intentional. Steering bypasses that waterfall and joins at its durable checkpoint.
+
 SDK users that need replayable transcript data should consume `session/event`; `agent/*` is the live coordination surface for queue/status, prompt interception, request shaping, steering, continuation, and errors.

 Maintenance mode: curated Mermaid sequence; exact event signatures live in the generated Cordis catalog.
--- 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: d7555368b583203cee664da3615c4fb4fb680c30
-architecture.zh.md: bafe59dee0559d5969c7400bdae85be0d012b3b5
+architecture.md: 6ff2aa1ad4ca2ef051322f9d95631fe626d26e84
+architecture.zh.md: b4b26efec16d85f1fb26589c5c9bffbb35e39564
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -28,6 +28,7 @@ Harnesses are [Cordis](cordis-primer.md) contexts whose packages contribute serv
 | `ctx.llm` | [`llm/`](../packages/llm/README.md) | adapter registry and streaming model calls |
 | `ctx.tokenMeter` | [`llm/token-meter`](../packages/llm/token-meter/README.md) | singleton replay-aware request/surface pressure |
 | `ctx.bash` | [`bash/`](../packages/bash/README.md) | foreground/background command execution |
+| `ctx.pty` | [`pty/`](../packages/pty/README.md) | owner-scoped persistent terminal sessions |
 | `ctx.sandbox` | [`sandbox/`](../packages/sandbox/README.md) | same-world process confinement (argv wrapping, per-call policy) |
 | `ctx.sandboxPolicy` | [`sandbox/`](../packages/sandbox/README.md) | shared sandbox policy home |
 | `ctx.codeRuntime` | [`code-runtime/`](../packages/code-runtime/README.md) | model-written program execution |
@@ -62,7 +63,7 @@ Waterfall events behave like around-middleware: a listener delegates by calling

 ## Default Loop Lifecycle

-The shipped loop drains prompt-to-checkpoint work through plugin-visible services and events.
+The shipped loop runs prompt-to-checkpoint work through plugin services and events.

 A **session** is append-only. Each ordinary **turn** claims one queued `send()` item; injection claims none. A successor awaits the preceding claimed turn's checkpoint but may share its `running` interval ([decision](../.agents/notes/implemented/simplification/2026-07-17-one-send-one-turn.md)). A turn ends when model and plugins stop it; a **step** is one model request plus tools. In the [sequence below](agent-lifecycle.md), quotes mark durable events.

@@ -80,17 +81,17 @@ forever:
  emit agent/status(running)
  TURN:
    'turn/start'
-    claimed message -> agent/prompt-submit
-      allowed prompt -> 'user/message' plus injected context
+    claimed message + contexts -> agent/prompt-submit
+      allowed prompt -> 'user/message' with prompt-prefix context baked in; append separate contexts
      blocked prompt -> 'prompt/blocked' -> 'turn/end'(rejected)
    STEP loop:
-      drain steering
+      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
      snapshot the derived messages (the reconstruction boundary)
      'step/start'
-      agent/request (config only) -> log request/header -> llm/stream (frozen)
+      agent/request (config only) -> log request/header -> checkpoint -> llm/stream (frozen)
      on final adapter-path or terminal in-band failure:
        'step/end'
        agent/request-error(original error, failure facts, immutable prior failures, signal)
@@ -102,10 +103,10 @@ forever:
        schedule tool calls by ctx.tools.executionMode:
          exclusive -> one-call barrier
          parallel -> rolling pool, <= maxParallelToolCalls in flight; reclassify before start
-          each start -> 'tool/call' -> ordered tools/pre-execute -> concurrent tools/execute
+          each start -> 'tool/call' -> ordered tools/pre-execute -> checkpoint -> concurrent tools/execute
          each model-order result -> ordered tools/post-execute -> 'tool/result'
        append accepted tool-batch context after all recorded results, then steering
-        agent/post-step
+        agent/post-step -> checkpoint complete response/results
        'step/end'
        agent/turn-continuation
        agent/turn-stop (terminal policy)
@@ -122,11 +123,11 @@ Pruning precedes summaries; overflow retries require durable progress. Bounded t

 ### Failure Boundaries

-The turn contains failures. Adapter failures close the step before `agent/request-error`, which receives exact `Error`, `LlmFailure`, and history. Retry opens another step; success clears history; exhaustion stores failure on `turn/end`. Failed chunks commit no message/tool.
+Adapter failures close the step before `agent/request-error` with exact `Error`, `LlmFailure`, and history. Retry opens another step; success clears history; exhaustion stores failure on `turn/end`. Failed chunks commit no message/tool.

 Other failures use `agent/error`. Cancellation and disposal beat recovery; undispatched tool calls get synthetic `tool/call`/`ABORTED_BEFORE_DISPATCH` pairs. The turn signal retires before `turn/end`. Effective `cancel()` emits its typed cause before clearing queues and aborting; observers cannot veto, idle calls emit nothing, and durability records `aborted`. Disposal awaits quiescence ([decision](../.agents/notes/implemented/architecture/2026-07-16-explicit-turn-cancellation.md)).

-Every session event is turn-enclosed. Reloading preserves an interrupted tail and closes it with a synthetic `interrupted` turn end. Failures after durable turn close report only through `agent/error` because no safe in-turn position remains. Each turn has one `TurnEndReason`; [TurnEndReasonMap](core-data-structures/session.md#why-a-turn-ended-turnendreasonmap) owns the variants.
+Session events are turn-enclosed. Reload closes an interrupted tail with a synthetic `interrupted` turn end. Post-close failures report only through `agent/error`; no safe in-turn position remains. Each turn has one `TurnEndReason`; [TurnEndReasonMap](core-data-structures/session.md#why-a-turn-ended-turnendreasonmap) owns the variants.

 ### Agent Handles

@@ -144,7 +145,7 @@ The session log is authoritative. `deriveMessages()` projects model history; raw

 **Model-visible ⟺ logged**: the log reconstructs every request — messages at `step/start` fronted by the header's session prefix, and headers by folding `request/header` — and the package-owned `dsh-agent-loop/invariant` can assert it through `ctx.invariants` ([reconstructability](../.agents/notes/implemented/architecture/2026-07-05-reconstructable-requests.md)).

-Durability is a plugin concern. Backends buffer synchronous `session/event` notifications; the loop awaits a turn-end checkpoint. `SessionPersistence` stores `SessionEvent` directly and metadata in `SessionHeader`; JSONL defaults to checksummed Zstandard, with SQLite under one contract.
+Durability is a plugin concern. Backends buffer synchronous `session/event` notifications. The semantic checkpoint policy drains requests before adapter dispatch, recorded top-level calls before tool dispatch, and complete response/result batches at `agent/post-step`; the loop retains the final turn-end checkpoint. `SessionPersistence` stores `SessionEvent` directly and metadata in `SessionHeader`; JSONL defaults to checksummed Zstandard, with SQLite under one contract ([decision](../.agents/notes/implemented/bug-fix/2026-07-21-semantic-session-checkpoints.md)).

 `ctx.sessions.appendOutOfBand()` joins plugin-owned log-only events to an open turn or creates a balanced, flushed zero-step turn. `session/title` folds latest-wins with source seqs and provenance; its immediate fallback and sole optional async provider never delay the agent response. Forks inherit titles ([decision](../.agents/notes/implemented/feature/2026-07-21-log-backed-session-titles.md)).

@@ -177,6 +178,7 @@ New behavior attaches to a documented extension point; a loop change updates thi
 | Add a model provider | register an adapter on `ctx.llm` |
 | Add a model-facing capability | register on `ctx.tools`; schemas enter prompt assembly |
 | Add shell execution | implement and register a `ctx.bash` backend |
+| Add persistent terminal execution | register a `ctx.pty` backend and `dsh-tool-pty` |
 | Add a human command | register on `ctx.commands`; adapters discover and dispatch it without a model turn |
 | Add background work | register on `ctx.tasks`; generic `task_*` tools collect or stop it |
 | Add filesystem access or policy | implement a `ctx.fs` provider or listen on `fs/*` policy events |
--- a/docs/architecture.zh.md
+++ b/docs/architecture.zh.md
@@ -28,6 +28,7 @@
 | `ctx.llm` | [`llm/`](../packages/llm/README.md) | 适配器注册表和模型流式调用 |
 | `ctx.tokenMeter` | [`llm/token-meter`](../packages/llm/token-meter/README.md) | 感知回放的单实例请求压力和会话表面压力 |
 | `ctx.bash` | [`bash/`](../packages/bash/README.md) | 前台和后台命令执行 |
+| `ctx.pty` | [`pty/`](../packages/pty/README.md) | 按 owner 隔离的持久化终端会话 |
 | `ctx.sandbox` | [`sandbox/`](../packages/sandbox/README.md) | 同一执行环境内的进程限制（argv 包装、逐调用策略） |
 | `ctx.sandboxPolicy` | [`sandbox/`](../packages/sandbox/README.md) | 共享沙箱策略归属点 |
 | `ctx.codeRuntime` | [`code-runtime/`](../packages/code-runtime/README.md) | 执行模型编写的程序 |
@@ -62,7 +63,7 @@ waterfall（瀑布式事件）的行为类似环绕中间件：监听器调用 `

 ## 默认循环生命周期

-已交付的循环通过插件可见的服务和事件，持续处理从提示词到检查点的工作。
+已交付的循环通过插件服务和事件，处理从提示词到检查点的工作。

 **会话**采用仅追加方式。每个普通**轮次**领取一项已排队的 `send()` 输入；注入不领取输入。后续轮次会等待前一个已领取轮次的检查点，但可以与其共用同一个 `running` 区间（[决策](../.agents/notes/implemented/simplification/2026-07-17-one-send-one-turn.md)）。模型和插件停止轮次时，该轮次结束；一个**步骤**包含一次模型请求及其工具。在[下文时序](agent-lifecycle.md)中，引号标记持久事件。

@@ -80,17 +81,17 @@ forever:
  emit agent/status(running)
  TURN:
    'turn/start'
-    claimed message -> agent/prompt-submit
-      allowed prompt -> 'user/message' plus injected context
+    claimed message + contexts -> agent/prompt-submit
+      allowed prompt -> 'user/message' with prompt-prefix context baked in; append separate contexts
      blocked prompt -> 'prompt/blocked' -> 'turn/end'(rejected)
    STEP loop:
-      drain steering
+      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
      snapshot the derived messages (the reconstruction boundary)
      'step/start'
-      agent/request (config only) -> log request/header -> llm/stream (frozen)
+      agent/request (config only) -> log request/header -> checkpoint -> llm/stream (frozen)
      on final adapter-path or terminal in-band failure:
        'step/end'
        agent/request-error(original error, failure facts, immutable prior failures, signal)
@@ -102,10 +103,10 @@ forever:
        schedule tool calls by ctx.tools.executionMode:
          exclusive -> one-call barrier
          parallel -> rolling pool, <= maxParallelToolCalls in flight; reclassify before start
-          each start -> 'tool/call' -> ordered tools/pre-execute -> concurrent tools/execute
+          each start -> 'tool/call' -> ordered tools/pre-execute -> checkpoint -> concurrent tools/execute
          each model-order result -> ordered tools/post-execute -> 'tool/result'
        append accepted tool-batch context after all recorded results, then steering
-        agent/post-step
+        agent/post-step -> checkpoint complete response/results
        'step/end'
        agent/turn-continuation
        agent/turn-stop (terminal policy)
@@ -122,11 +123,11 @@ forever:

 ### 失败边界

-轮次负责隔离故障。适配器故障会先关闭步骤，再进入 `agent/request-error`；该事件会收到准确的 `Error`、`LlmFailure` 和历史记录。重试会开启另一个步骤；成功会清除历史记录；重试耗尽后，故障存入 `turn/end`。失败分片不会提交消息或工具。
+适配器故障会先关闭步骤，再进入 `agent/request-error`；该事件会收到准确的 `Error`、`LlmFailure` 和历史记录。重试会开启另一个步骤；成功会清除历史记录；重试耗尽后，故障存入 `turn/end`。失败分片不会提交消息或工具。

 其他故障使用 `agent/error`。取消和资源释放均优先于恢复；尚未分派的工具调用会得到合成的 `tool/call`/`ABORTED_BEFORE_DISPATCH` 对。轮次信号会在 `turn/end` 前失效。实际生效的 `cancel()` 会在清空队列和中止前发出类型化原因；观察方不能否决该操作，空闲状态下的调用不发出任何事件，持久化会记录 `aborted`。dispose（资源释放）会等待系统停稳（[决策](../.agents/notes/implemented/architecture/2026-07-16-explicit-turn-cancellation.md)）。

-每个会话事件都包围在轮次内。重新加载会保留中断的日志尾部，并用合成的 `interrupted` 轮次结束事件将其闭合。持久轮次关闭后的故障只通过 `agent/error` 报告，因为此时已没有安全的轮次内位置。每个轮次有一个 `TurnEndReason`；各变体由 [TurnEndReasonMap](core-data-structures/session.md#why-a-turn-ended-turnendreasonmap) 统一定义。
+会话事件均位于轮次边界内。重新加载会用合成的 `interrupted` 轮次结束事件闭合中断的日志尾部。关闭后的故障只通过 `agent/error` 报告；此时已没有安全的轮次内位置。每个轮次有一个 `TurnEndReason`；各变体由 [TurnEndReasonMap](core-data-structures/session.md#why-a-turn-ended-turnendreasonmap) 统一定义。

 ### Agent 句柄

@@ -144,7 +145,7 @@ forever:

 **模型可见 ⟺ 已记录**：日志可以重建每个请求，包括由请求头会话前缀置于开头的 `step/start` 时消息，以及通过折叠 `request/header` 得到的请求头；开发期不变量会断言这一点（[可重建性](../.agents/notes/implemented/architecture/2026-07-05-reconstructable-requests.md)）。

-持久性由插件负责。后端会缓冲同步的 `session/event` 通知；循环等待轮次结束检查点。`SessionPersistence` 直接存储 `SessionEvent`，并将元数据存入 `SessionHeader`；JSONL 默认采用带校验和的 Zstandard，SQLite 则遵循同一契约。
+持久性由插件负责。后端会缓冲同步的 `session/event` 通知。语义检查点策略会在适配器分发前刷写请求，在工具分发前刷写已记录的顶层调用，并在 `agent/post-step` 刷写完整的响应与结果批次；循环仍保留最终的轮次结束检查点。`SessionPersistence` 直接存储 `SessionEvent`，并将元数据存入 `SessionHeader`；JSONL 默认采用带校验和的 Zstandard，SQLite 则遵循同一契约（[决策](../.agents/notes/implemented/bug-fix/2026-07-21-semantic-session-checkpoints.md)）。

 `ctx.sessions.appendOutOfBand()` 会把插件所属的纯日志事件加入开放轮次，或创建一个平衡且已刷写的零步骤轮次。`session/title` 按后写覆盖方式折叠，并携带源 seq 和来源信息；其即时回退标题和唯一可选异步提供方都不会延迟 agent 响应。fork 会继承标题（[决策](../.agents/notes/implemented/feature/2026-07-21-log-backed-session-titles.md)）。

@@ -177,6 +178,7 @@ forever:
 | 添加模型提供方 | 在 `ctx.llm` 上注册适配器 |
 | 添加面向模型的功能 | 在 `ctx.tools` 上注册；schema 进入提示词组装流程 |
 | 添加 shell 执行 | 实现并注册 `ctx.bash` 后端 |
+| 添加持久化终端执行 | 注册 `ctx.pty` 后端和 `dsh-tool-pty` |
 | 添加用户命令 | 在 `ctx.commands` 上注册；适配器无需模型轮次即可发现并分派该命令 |
 | 添加后台工作 | 在 `ctx.tasks` 上注册；通用 `task_*` 工具负责收集或停止 |
 | 添加文件系统访问或策略 | 实现 `ctx.fs` 提供方，或监听 `fs/*` 策略事件 |
--- a/docs/capability-seams.md
+++ b/docs/capability-seams.md
@@ -36,6 +36,9 @@ flowchart LR
  pkg_hooks_codex["hooks-codex"]
  pkg_acp["acp"]
  svc_sessionQuery["ctx.sessionQuery<br/>Exact session-history reads and traces"]
+  pkg_session_reference["session-reference"]
+  svc_sessionReferences["ctx.sessionReferences<br/>Cross-session snapshot preparation"]
+  pkg_tui["tui"]
  pkg_session_title["session-title"]
  svc_sessionTitle["ctx.sessionTitle<br/>Log-backed session titles"]
  pkg_session_title_first_message_llm["session-title-first-message-llm"]
@@ -44,6 +47,7 @@ flowchart LR
  svc_systemPrompt["ctx.systemPrompt<br/>System prompt assembly registry"]
  pkg_tools["tools"]
  pkg_tool_fs["tool-fs"]
+  pkg_tool_pty["tool-pty"]
  pkg_tool_web["tool-web"]
  svc_tools["ctx.tools<br/>Tool registry and guarded execution pipeline"]
  pkg_tool_ask_user["tool-ask-user"]
@@ -53,7 +57,6 @@ flowchart LR
  pkg_tool_todo["tool-todo"]
  pkg_user_interaction["user-interaction"]
  svc_userInteraction["ctx.userInteraction<br/>Human question/answer seam"]
-  pkg_tui["tui"]
  pkg_plan_mode["plan-mode"]
  svc_planMode["ctx.planMode<br/>Plan collaboration state"]
  pkg_commands["commands"]
@@ -72,6 +75,9 @@ flowchart LR
  pkg_bash_local["bash-local"]
  pkg_bash_sandbox["bash-sandbox"]
  svc_bashEnv["ctx.bashEnv<br/>Managed bash environment registry"]
+  pkg_pty["pty"]
+  svc_pty["ctx.pty<br/>Persistent PTY session registry"]
+  pkg_pty_local["pty-local"]
  pkg_sandbox["sandbox"]
  svc_sandbox["ctx.sandbox<br/>Process-sandbox seam"]
  pkg_sandbox_local["sandbox-local"]
@@ -139,6 +145,8 @@ flowchart LR
  pkg_llm_replay --> svc_llm
  pkg_permission --> svc_permission
  pkg_plan_mode --> svc_planMode
+  pkg_pty --> svc_pty
+  pkg_pty_local --> svc_pty
  pkg_sandbox --> svc_sandbox
  pkg_sandbox_local --> svc_sandbox
  pkg_sandbox_policy --> svc_sandboxPolicy
@@ -147,6 +155,7 @@ flowchart LR
  pkg_session_persistence_jsonl --> svc_sessionPersistence
  pkg_session_persistence_sqlite --> svc_sessionPersistence
  pkg_session_query --> svc_sessionQuery
+  pkg_session_reference --> svc_sessionReferences
  pkg_session_title --> svc_sessionTitle
  pkg_session_title_all_messages_llm --> svc_sessionTitle
  pkg_session_title_first_message_llm --> svc_sessionTitle
@@ -196,15 +205,21 @@ flowchart LR
  svc_llm --> pkg_compact_basic
  svc_permission --> pkg_acp
  svc_planMode --> pkg_acp
+  svc_pty --> pkg_tool_pty
  svc_sandbox --> pkg_bash_sandbox
+  svc_sandbox --> pkg_pty_local
  svc_sandboxPolicy --> pkg_bash_sandbox
  svc_sandboxPolicy --> pkg_fs_sandbox
+  svc_sandboxPolicy --> pkg_pty_local
  svc_sessionPersistence --> pkg_acp
  svc_sessionPersistence --> pkg_agent_loop
  svc_sessionPersistence --> pkg_hooks_claude
  svc_sessionPersistence --> pkg_hooks_codex
  svc_sessionPersistence --> pkg_session_query
  svc_sessionPersistence --> pkg_tool_bash
+  svc_sessionQuery --> pkg_session_reference
+  svc_sessionReferences --> pkg_acp
+  svc_sessionReferences --> pkg_tui
  svc_sessions --> pkg_agent
  svc_sessions --> pkg_agent_loop
  svc_sessions --> pkg_cli_demo
@@ -217,9 +232,11 @@ flowchart LR
  svc_subagents --> pkg_tool_subagent
  svc_systemPrompt --> pkg_agent_loop
  svc_systemPrompt --> pkg_tool_fs
+  svc_systemPrompt --> pkg_tool_pty
  svc_systemPrompt --> pkg_tool_web
  svc_systemPrompt --> pkg_tools
  svc_tasks --> pkg_tool_bash
+  svc_tasks --> pkg_tool_pty
  svc_tasks --> pkg_tool_subagent
  svc_tasks --> pkg_tool_tasks
  svc_tokenMeter --> pkg_compact_basic
@@ -230,6 +247,7 @@ flowchart LR
  svc_tools --> pkg_tool_bash
  svc_tools --> pkg_tool_cordis
  svc_tools --> pkg_tool_fs
+  svc_tools --> pkg_tool_pty
  svc_tools --> pkg_tool_skill
  svc_tools --> pkg_tool_subagent
  svc_tools --> pkg_tool_todo
@@ -251,10 +269,11 @@ flowchart LR
 | `ctx.sessions` | `core` | [`session`](../packages/core/session) | - | [`agent-loop`](../packages/core/agent-loop), [`agent`](../packages/core/agent), [`cli-demo`](../packages/examples/cli-demo), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-query`](../packages/session-query/session-query), [`subagent-inprocess`](../packages/subagent/subagent-inprocess) | - | Owns append-only Session instances and emits the durable session event feed. |
 | `ctx.invariants` | `core` | [`invariants`](../packages/support/invariants) | - | [`session`](../packages/core/session), [`agent`](../packages/core/agent), [`scope`](../packages/core/scope), [`agent-loop`](../packages/core/agent-loop) | - | Companion subpaths register owner-local checks; the service owns selection, uniqueness, child fibers, and package-attributed failures. |
 | `ctx.sessionPersistence` | `seam` | [`session-persistence`](../packages/session-persistence/session-persistence) | [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`session-persistence-sqlite`](../packages/session-persistence/session-persistence-sqlite) | [`agent-loop`](../packages/core/agent-loop), [`tool-bash`](../packages/bash/tool-bash), [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex), [`acp`](../packages/ui/acp), [`session-query`](../packages/session-query/session-query) | - | Backends persist the same SessionEvent vocabulary; apps choose a backend at composition time. |
-| `ctx.sessionQuery` | `seam` | [`session-query`](../packages/session-query/session-query) | - | - | - | Resolves live and optional persisted logs into one logical corpus for exact reads and relationship traces. |
+| `ctx.sessionQuery` | `seam` | [`session-query`](../packages/session-query/session-query) | - | [`session-reference`](../packages/context/session-reference) | - | Resolves live and optional persisted logs into one logical corpus for exact reads and relationship traces. |
+| `ctx.sessionReferences` | `core` | [`session-reference`](../packages/context/session-reference) | - | [`tui`](../packages/ui/tui), [`acp`](../packages/ui/acp) | - | Projects bounded current-surface conversation snapshots into durable untrusted message context; host adapters own mention syntax. |
 | `ctx.sessionTitle` | `seam` | [`session-title`](../packages/session-title/session-title) | [`session-title-first-message-llm`](../packages/session-title/session-title-first-message-llm), [`session-title-all-messages-llm`](../packages/session-title/session-title-all-messages-llm) | - | - | Owns the deterministic fallback, latest-title fold, and sole optional asynchronous provider registration. |
-| `ctx.systemPrompt` | `core` | [`system-prompt`](../packages/core/system-prompt) | - | [`agent-loop`](../packages/core/agent-loop), [`tools`](../packages/core/tools), [`tool-fs`](../packages/fs/tool-fs), [`tool-web`](../packages/web/tool-web) | - | Collects prompt sections and model-facing tool schemas for each step. |
-| `ctx.tools` | `core` | [`tools`](../packages/core/tools) | - | [`agent-loop`](../packages/core/agent-loop), [`tool-ask-user`](../packages/ui/tool-ask-user), [`tool-bash`](../packages/bash/tool-bash), [`tool-cordis`](../packages/cordis/tool-cordis), [`tool-fs`](../packages/fs/tool-fs), [`tool-skill`](../packages/skill/tool-skill), [`tool-subagent`](../packages/subagent/tool-subagent), [`tool-todo`](../packages/todo/tool-todo), [`tool-web`](../packages/web/tool-web), [`acp`](../packages/ui/acp) | - | Registers capabilities, owns Code Mode transport, and routes calls through pre-policy, monotonic guards, around dispatch, post-policy, and final-result observation. |
+| `ctx.systemPrompt` | `core` | [`system-prompt`](../packages/core/system-prompt) | - | [`agent-loop`](../packages/core/agent-loop), [`tools`](../packages/core/tools), [`tool-fs`](../packages/fs/tool-fs), [`tool-pty`](../packages/pty/tool-pty), [`tool-web`](../packages/web/tool-web) | - | Collects prompt sections and model-facing tool schemas for each step. |
+| `ctx.tools` | `core` | [`tools`](../packages/core/tools) | - | [`agent-loop`](../packages/core/agent-loop), [`tool-ask-user`](../packages/ui/tool-ask-user), [`tool-bash`](../packages/bash/tool-bash), [`tool-cordis`](../packages/cordis/tool-cordis), [`tool-fs`](../packages/fs/tool-fs), [`tool-pty`](../packages/pty/tool-pty), [`tool-skill`](../packages/skill/tool-skill), [`tool-subagent`](../packages/subagent/tool-subagent), [`tool-todo`](../packages/todo/tool-todo), [`tool-web`](../packages/web/tool-web), [`acp`](../packages/ui/acp) | - | Registers capabilities, owns Code Mode transport, and routes calls through pre-policy, monotonic guards, around dispatch, post-policy, and final-result observation. |
 | `ctx.userInteraction` | `seam` | [`user-interaction`](../packages/ui/user-interaction) | [`tui`](../packages/ui/tui), [`acp`](../packages/ui/acp) | [`tool-ask-user`](../packages/ui/tool-ask-user), [`tui`](../packages/ui/tui), [`acp`](../packages/ui/acp) | - | UI front doors provide the active human-answer provider; tool-ask-user pauses a tool call on the provider-neutral ask() promise. |
 | `ctx.planMode` | `core` | [`plan-mode`](../packages/plan/plan-mode) | - | [`acp`](../packages/ui/acp) | - | Folds logged plan/mode state, flushes user selections at turn boundaries, renders deployment-owned guidance, registers /plan, and keeps the plan-exit schema stable across transitions. |
 | `ctx.commands` | `core` | [`commands`](../packages/ui/commands) | - | [`tui`](../packages/ui/tui), [`acp`](../packages/ui/acp) | - | Plugins register direct human commands; TUI and ACP consume the same effective per-agent catalog without sending invocations to the model. |
@@ -264,15 +283,16 @@ flowchart LR
 | `ctx.goals` | `core` | [`goal`](../packages/goal/goal) | - | - | - | Folds revisioned objective state from the session log and keeps live continuation activation process-local. |
 | `ctx.bash` | `seam` | [`bash`](../packages/bash/bash) | [`bash-local`](../packages/bash/bash-local), [`bash-sandbox`](../packages/bash/bash-sandbox) | [`tool-bash`](../packages/bash/tool-bash), [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex) | - | The model-facing bash tools and hook bridges consume this seam; sandboxed or remote executors replace bash-local without touching them. |
 | `ctx.bashEnv` | `core` | [`tool-bash`](../packages/bash/tool-bash) | - | - | - | Plugins declare effect-scoped DSH_* facts; tool-bash collects one trusted snapshot per execution and the executor rebuilds the namespace. |
-| `ctx.sandbox` | `seam` | [`sandbox`](../packages/sandbox/sandbox) | [`sandbox-local`](../packages/sandbox/sandbox-local) | [`bash-sandbox`](../packages/bash/bash-sandbox) | - | Consumers hand over the exact argv they are about to spawn; same-world backends wrap it under a per-call policy and report enforcement. |
-| `ctx.sandboxPolicy` | `core` | [`sandbox-policy`](../packages/sandbox/sandbox-policy) | - | [`bash-sandbox`](../packages/bash/bash-sandbox), [`fs-sandbox`](../packages/fs/fs-sandbox) | - | The one home for the deployment default mode + workspace root; only the sandboxed executor and provider read the service (the tool layers use the pure `sandbox/mode` fold it also exports). Both enforcing families read it so bash and fs cannot confine to different roots. |
+| `ctx.pty` | `seam` | [`pty`](../packages/pty/pty) | [`pty-local`](../packages/pty/pty-local) | [`tool-pty`](../packages/pty/tool-pty) | - | The registry owns exact-Agent session identity and cleanup; backends own terminal mechanics, while tool-pty exposes the owner-scoped model surface. |
+| `ctx.sandbox` | `seam` | [`sandbox`](../packages/sandbox/sandbox) | [`sandbox-local`](../packages/sandbox/sandbox-local) | [`bash-sandbox`](../packages/bash/bash-sandbox), [`pty-local`](../packages/pty/pty-local) | - | Consumers hand over the exact argv they are about to spawn; same-world backends wrap it under a per-call policy and report enforcement. |
+| `ctx.sandboxPolicy` | `core` | [`sandbox-policy`](../packages/sandbox/sandbox-policy) | - | [`bash-sandbox`](../packages/bash/bash-sandbox), [`fs-sandbox`](../packages/fs/fs-sandbox), [`pty-local`](../packages/pty/pty-local) | - | The one home for the deployment default mode + workspace root; only the sandboxed executor and provider read the service (the tool layers use the pure `sandbox/mode` fold it also exports). Both enforcing families read it so bash and fs cannot confine to different roots. |
 | `ctx.approval` | `seam` | `approval` | [`acp`](../packages/ui/acp) | [`tools`](../packages/core/tools), [`tool-bash`](../packages/bash/tool-bash) | - | One-shot permission decisions dispatched over the `approval/request` waterfall; answerers are listeners (the ACP bridge for its own agents), absence fails closed to `unavailable`. |
 | `ctx.permission` | `core` | [`permission`](../packages/ui/permission) | - | [`acp`](../packages/ui/acp) | - | User-facing preset table (`workspace-write`/`danger-full-access`) bundling the sandbox-mode and approval-policy knobs; a switch writes one `permission/preset` event through to both knob events. |
 | `ctx.codeRuntime` | `seam` | [`code-runtime`](../packages/code-runtime/code-runtime) | [`code-runtime-worker`](../packages/code-runtime/code-runtime-worker) | [`tools`](../packages/core/tools) | - | Runs one model-written program against host-provided async bindings; backends differ by substrate and language (the tool registry consumes it for Code Mode). |
 | `ctx.fs` | `seam` | [`fs`](../packages/fs/fs) | [`fs-local`](../packages/fs/fs-local), [`fs-sandbox`](../packages/fs/fs-sandbox) | [`tool-fs`](../packages/fs/tool-fs) | [`fs-policy`](../packages/fs/fs-policy) | tool-fs executes read/write/edit through ctx.fs; fs-sandbox fences mutations by the shared sandbox mode; fs-policy contributes observed-state checks through the fs/* event gate. |
 | `ctx.compact` | `seam` | [`compact`](../packages/compact/compact) | [`compact-basic`](../packages/compact/compact-basic) | [`compact-basic`](../packages/compact/compact-basic) | - | The basic backend consumes post-step pressure and request-error recovery events; a model-facing compact tool remains deferred. |
 | `ctx.subagents` | `seam` | [`subagent`](../packages/subagent/subagent) | [`subagent-spawn`](../packages/subagent/subagent-spawn), [`subagent-fork`](../packages/subagent/subagent-fork), [`subagent-acp`](../packages/subagent/subagent-acp) | [`tool-subagent`](../packages/subagent/tool-subagent), [`tool-ralph`](../packages/workflow/tool-ralph) | - | Providers implement transports; tool-subagent exposes configured delegation while tool-ralph requires one fresh structured-output route. |
-| `ctx.tasks` | `core` | [`tasks`](../packages/tasks/tasks) | - | [`tool-bash`](../packages/bash/tool-bash), [`tool-subagent`](../packages/subagent/tool-subagent), [`tool-tasks`](../packages/tasks/tool-tasks) | - | Producers (tool-bash background commands, tool-subagent background delegations) register running work; tool-tasks is the model-facing control surface that reads, lists, and kills it. |
+| `ctx.tasks` | `core` | [`tasks`](../packages/tasks/tasks) | - | [`tool-bash`](../packages/bash/tool-bash), [`tool-pty`](../packages/pty/tool-pty), [`tool-subagent`](../packages/subagent/tool-subagent), [`tool-tasks`](../packages/tasks/tool-tasks) | - | Producers (background bash, PTY sends, and subagent delegations) register running work; tool-tasks is the model-facing control surface that reads, lists, and kills it. |
 | `ctx.web` | `seam` | [`web`](../packages/web/web) | [`web-search-exa`](../packages/web/web-search-exa), [`web-search-perplexity`](../packages/web/web-search-perplexity), [`web-search-deepseek`](../packages/web/web-search-deepseek), [`web-fetch-local`](../packages/web/web-fetch-local) | [`tool-web`](../packages/web/tool-web) | - | Search and fetch providers register into one ctx.web seam; tool-web owns the stable model-facing names. |
 | `ctx.spillStore` | `seam` | [`spill`](../packages/spill/spill) | [`spill-local`](../packages/spill/spill-local) | [`spill-policy`](../packages/spill/spill-policy) | - | The backend saves oversized tool text and returns a model-facing locator plus retrieval hint; spill-policy is the tools/post-execute consumer that decides when to spill. |
 | `ctx.workflows` | `seam` | [`workflow`](../packages/workflow/workflow) | [`workflow-workerthread`](../packages/workflow/workflow-workerthread) | [`tool-workflow`](../packages/workflow/tool-workflow), [`tool-ralph`](../packages/workflow/tool-ralph) | - | One engine per context (bash shape, no named-provider registry); the general workflow and fixed Ralph consumers start runs whose agent() calls fan out through ctx.subagents. |
--- 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:275`](../packages/ui/acp/src/index.ts)
+Source: [`packages/ui/acp/src/index.ts:285`](../packages/ui/acp/src/index.ts)

 ## `@deepseek-ai/dsh-acp-demo`

@@ -60,8 +60,12 @@ export interface Config {
  sessionTitle?: NonNullable<agentCore.Config['sessionTitle']>
  /** Directory the JSONL session backend writes under. Defaults to `./.sessions`. */
  persistenceRoot?: string
+  /** Write delta-chunk runs as packed storage rows (the JSONL backend's `packChunks`). Defaults to `false`. */
+  packChunks?: boolean
  /** JSONL artifact encoding; defaults to checksummed Zstandard frames. */
  persistenceCompression?: JsonlCompression
+  /** Cross-session reference discovery and snapshot byte budgets. */
+  sessionReferences?: SessionReferenceConfig
  /** Controls automatic AGENTS.md/CLAUDE.md loading; configure a byte budget or set `false`. */
  workspaceContext: agentCore.Config['workspaceContext']
  /** Skill registry, local-provider, and model-facing consumer config forwarded to agent-spine-demo. */
@@ -77,9 +81,9 @@ export interface Config {
 }
 ```

-Depends on: [`agentCore`](../packages/examples/agent-spine-demo/src/index.ts) · [`JsonlCompression`](../packages/session-persistence/session-persistence-jsonl/src/index.ts) · [`ToolsConfig`](#deepseek-aidsh-tools)
+Depends on: [`agentCore`](../packages/examples/agent-spine-demo/src/index.ts) · [`JsonlCompression`](../packages/session-persistence/session-persistence-jsonl/src/index.ts) · [`SessionReferenceConfig`](#deepseek-aidsh-session-reference) · [`ToolsConfig`](#deepseek-aidsh-tools)

-Source: [`packages/examples/acp-demo/src/index.ts:38`](../packages/examples/acp-demo/src/index.ts)
+Source: [`packages/examples/acp-demo/src/index.ts:43`](../packages/examples/acp-demo/src/index.ts)

 ## `@deepseek-ai/dsh-agent-loop`

@@ -218,11 +222,10 @@ Requires: `sandbox` · `sandboxPolicy`
 ```ts config-catalog
 /**
 * Plugin config: the local executor's knobs, verbatim. The sandbox policy —
- * the default mode and the `workspace-write` boundary root — is NOT here: it
- * lives on `ctx.sandboxPolicy` (`@deepseek-ai/dsh-sandbox-policy`), the one
- * home both enforcing families read, so bash and fs can never confine to
- * different roots. The runner choice is likewise the `ctx.sandbox` provider's
- * config, not this executor's.
+ * the default mode and fallback `workspace-write` root — is NOT here: it lives
+ * on `ctx.sandboxPolicy` (`@deepseek-ai/dsh-sandbox-policy`), which resolves
+ * each calling session's mode and cwd for both enforcing families. The runner
+ * choice is likewise the `ctx.sandbox` provider's config, not this executor's.
 */
 export type Config = LocalConfig
 ```
@@ -271,7 +274,7 @@ export interface Config {

 Depends on: [`agentCore`](../packages/examples/agent-spine-demo/src/index.ts) · [`JsonlCompression`](../packages/session-persistence/session-persistence-jsonl/src/index.ts) · [`ToolsConfig`](#deepseek-aidsh-tools)

-Source: [`packages/examples/cli-demo/src/index.ts:25`](../packages/examples/cli-demo/src/index.ts)
+Source: [`packages/examples/cli-demo/src/index.ts:26`](../packages/examples/cli-demo/src/index.ts)

 ## `@deepseek-ai/dsh-code-runtime-worker`

@@ -389,8 +392,8 @@ Requires: `sandboxPolicy`
 /**
 * Plugin config: the local backend's knobs, verbatim (only `cwd`, the resolve
 * base for relative paths). The sandbox default (mode + `workspace-write`
- * boundary root) is NOT here — it lives on `ctx.sandboxPolicy`, the one home
- * both enforcing families share.
+ * fallback root) is NOT here — `ctx.sandboxPolicy` resolves each calling
+ * session for both enforcing families.
 */
 export type Config = LocalConfig
 ```
@@ -639,7 +642,7 @@ export interface ReplayModelConfig {
 }
 ```

-Source: [`packages/support/llm-replay/src/index.ts:385`](../packages/support/llm-replay/src/index.ts)
+Source: [`packages/support/llm-replay/src/index.ts:387`](../packages/support/llm-replay/src/index.ts)

 ## `@deepseek-ai/dsh-llm-retry`

@@ -800,6 +803,44 @@ export interface PlanModeConfig {

 Source: [`packages/plan/plan-mode/src/index.ts:57`](../packages/plan/plan-mode/src/index.ts)

+## `@deepseek-ai/dsh-pty-local`
+
+Requires: `pty` · `sandbox` · `sandboxPolicy`
+
+```ts config-catalog
+/** Public plugin configuration. */
+export interface Config {
+  /** Backend registry type (default: `shell`). */
+  backendType?: string
+  /** Interactive shell executable (default: `/bin/bash`). */
+  shellPath?: string
+  /** Shell arguments (default: `--noprofile --norc -i`). */
+  shellArgs?: string[]
+  /** Terminal rows. */
+  rows?: number
+  /** Terminal columns. */
+  cols?: number
+  /** Maximum retained logical lines. */
+  scrollbackLines?: number
+  /** Maximum retained UTF-8 bytes. */
+  scrollbackMaxBytes?: number
+  /** Maximum bytes returned by one read or settled viewport. */
+  maxReadBytes?: number
+  /** Readiness polling interval. */
+  pollIntervalMs?: number
+  /** Delay before Linux exact syscall probes. */
+  exactProbeAfterMs?: number
+  /** Silence duration that yields `inferred_idle`. */
+  idleSilenceMs?: number
+  /** Absolute send wait bound. */
+  timeoutMs?: number
+  /** Grace before teardown escalates to `SIGKILL`. */
+  disposeGraceMs?: number
+}
+```
+
+Source: [`packages/pty/pty-local/src/config.ts:6`](../packages/pty/pty-local/src/config.ts)
+
 ## `@deepseek-ai/dsh-repeat-tool-guard`

 ```ts config-catalog
@@ -874,8 +915,8 @@ export interface Config {
  /** File-sandbox mode a session starts from (default: `read-only`). */
  mode?: SandboxMode
  /**
-   * Absolute root directory `workspace-write` may write under (default:
-   * `process.cwd()`). Both enforcing families fence against this SAME root.
+   * Fallback root for agentless calls and sessions without a cwd (default:
+   * `process.cwd()`). Normal agent calls use their session cwd instead.
   */
  workspaceRoot?: string
 }
@@ -890,7 +931,7 @@ Source: [`packages/sandbox/sandbox-policy/src/index.ts:44`](../packages/sandbox/
 Requires: `sessions`

 ```ts config-catalog
-/** Plugin config: where the JSONL backend keeps its session logs (`root` is required — no default). */
+/** Plugin config: where the JSONL backend keeps its session logs, and the packed-row write switch. */
 export interface Config {
  /**
   * Root directory for all session files. Required (no default): a default of
@@ -898,6 +939,15 @@ export interface Config {
   * (bash calls, subprocesses). Sessions group under per-cwd subdirectories.
   */
  root: string
+  /**
+   * Write runs of consecutive `assistant/chunk` delta events as packed
+   * `text-chunks`/`reasoning-chunks`/`tool-call-chunks` rows (lossless,
+   * ~60% smaller logs measured on a real session). Off by default while
+   * snapshot fixtures stay in the one-event-per-line layout: recording with
+   * packing on rewrites every golden `session.jsonl`. READING packed rows is
+   * unconditional — a log's layout never depends on this switch.
+   */
+  packChunks?: boolean
  /** Physical encoding; defaults to checksummed Zstandard frames. */
  compression?: JsonlCompression
 }
@@ -961,6 +1011,24 @@ export interface Config {

 Source: [`packages/session-query/session-query/src/config.ts:9`](../packages/session-query/session-query/src/config.ts)

+## `@deepseek-ai/dsh-session-reference`
+
+Requires: `sessionQuery`
+
+```ts config-catalog
+/** Session-reference service configuration. */
+export interface Config {
+  /** Maximum distinct source sessions referenced by one message, from one to three. */
+  maxReferences?: number
+  /** Default host candidate-list limit. */
+  candidateLimit?: number
+  /** Maximum rendered UTF-8 bytes for one source snapshot. */
+  maxReferenceBytes?: number
+}
+```
+
+Source: [`packages/context/session-reference/src/config.ts:11`](../packages/context/session-reference/src/config.ts)
+
 ## `@deepseek-ai/dsh-session-title`

 Requires: `sessions`
@@ -977,7 +1045,7 @@ 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`

@@ -1474,10 +1542,18 @@ Requires: `agents` · `commands` · `userInteraction` · `tools` · `llm` · `sy
 ```ts config-catalog
 /** Serializable plugin configuration. */
 export interface Config extends TuiConfig {
-  /** Header subtitle. Defaults to `ready.`. */
+  /** Banner subtitle line. When absent, the banner has no subtitle and sweeps in on start. */
  welcome?: string
  /** Exact shared agent/session identity driven by this terminal. Defaults to `main`. */
  sessionId?: string
+  /**
+   * Shell command template shown for resuming this session: printed on exit and
+   * listed by `/resume`, with every `{session}` occurrence replaced by the live
+   * session id. Absent disables both surfaces. Deployments set it only when a
+   * persistence backend makes the session resumable (e.g.
+   * `RESUME_SESSION_ID={session} dsh`).
+   */
+  resumeCommand?: string
 }

 /** Presentation settings for the pi-tui terminal mode. */
@@ -1502,12 +1578,19 @@ export interface TuiConfig {
  showHardwareCursor?: boolean
  /** Apply the built-in ANSI color palette. */
  color?: boolean
-  /** Terminal window title while the UI is mounted. */
+  /**
+   * Paint the startup banner's product name in the DeepSeek brand gradient
+   * using 24-bit truecolor. Requires {@link TuiConfig.color}; falls back to the
+   * flat accent color when either is off. Unset auto-detects `COLORTERM` at the
+   * process boundary, so most deployments leave it unset.
+   */
+  truecolor?: boolean
+  /** Terminal window title while the UI is mounted; a logged session title prefixes it. */
  title?: string
 }
 ```

-Source: [`packages/ui/tui/src/index.ts:129`](../packages/ui/tui/src/index.ts)
+Source: [`packages/ui/tui/src/index.ts:161`](../packages/ui/tui/src/index.ts)

 ## `@deepseek-ai/dsh-tui-demo`

@@ -1534,8 +1617,17 @@ export interface Config {
  persistenceRoot?: string
  /** JSONL artifact encoding; defaults to checksummed Zstandard frames. */
  persistenceCompression?: JsonlCompression
-  /** TUI subtitle rendered on start. Defaults to `ready.`. */
+  /** Cross-session reference discovery and snapshot byte budgets. */
+  sessionReferences?: SessionReferenceConfig
+  /** TUI transcript's optional first line; absent renders nothing on start. */
  welcome?: string
+  /**
+   * Shell command template the TUI prints on exit and lists under `/resume`,
+   * with `{session}` replaced by the live session id (forwarded to the front
+   * door). Set it to a command that resumes via this app's env var, e.g.
+   * `RESUME_SESSION_ID={session} dsh`.
+   */
+  resumeCommand?: string
  /** Full-screen TUI presentation settings. */
  ui?: uiTui.TuiConfig
  /** Skill registry, local-provider, and model-facing consumer config. */
@@ -1553,9 +1645,9 @@ export interface Config {
 }
 ```

-Depends on: [`agentCore`](../packages/examples/agent-spine-demo/src/index.ts) · [`JsonlCompression`](../packages/session-persistence/session-persistence-jsonl/src/index.ts) · [`ToolsConfig`](#deepseek-aidsh-tools) · [`uiTui`](../packages/ui/tui/src/index.ts)
+Depends on: [`agentCore`](../packages/examples/agent-spine-demo/src/index.ts) · [`JsonlCompression`](../packages/session-persistence/session-persistence-jsonl/src/index.ts) · [`SessionReferenceConfig`](#deepseek-aidsh-session-reference) · [`ToolsConfig`](#deepseek-aidsh-tools) · [`uiTui`](../packages/ui/tui/src/index.ts)

-Source: [`packages/examples/tui-demo/src/index.ts:33`](../packages/examples/tui-demo/src/index.ts)
+Source: [`packages/examples/tui-demo/src/index.ts:38`](../packages/examples/tui-demo/src/index.ts)

 ## `@deepseek-ai/dsh-user-approval`

@@ -1740,12 +1832,20 @@ export interface Config {
  maxBytes: number
  /** Maximum UTF-8 bytes read from one instruction file; larger files are ignored. */
  maxSourceBytes?: number
-  /** Ordered same-directory project candidates; the first existing regular file wins in each scope. */
+  /**
+   * Ordered same-directory project candidates; every existing file loads, with
+   * per-directory trimmed-content duplicates collapsed to the earliest candidate.
+   */
  instructionFileCandidates?: string[]
+  /**
+   * Ordered same-directory local-overlay candidates loaded after the base files
+   * under the same per-directory trimmed-content dedup; empty disables the overlay.
+   */
+  localInstructionFileCandidates?: string[]
 }
 ```

-Source: [`packages/context/workspace-context/src/config.ts:16`](../packages/context/workspace-context/src/config.ts)
+Source: [`packages/context/workspace-context/src/config.ts:17`](../packages/context/workspace-context/src/config.ts)

 ## Loadable plugins with no config

@@ -1766,11 +1866,14 @@ These load from a `cordis.yml` entry with no `config:` block; they declare no co
 - `@deepseek-ai/dsh-goal-session` — requires `agents` · `goals` · `sessions` ([`packages/goal/goal-session/src/index.ts`](../packages/goal/goal-session/src/index.ts))
 - `@deepseek-ai/dsh-llm` ([`packages/llm/llm/src/index.ts`](../packages/llm/llm/src/index.ts))
 - `@deepseek-ai/dsh-lsp` ([`packages/lsp/lsp/src/index.ts`](../packages/lsp/lsp/src/index.ts))
+- `@deepseek-ai/dsh-pty` ([`packages/pty/pty/src/index.ts`](../packages/pty/pty/src/index.ts))
 - `@deepseek-ai/dsh-session` ([`packages/core/session/src/index.ts`](../packages/core/session/src/index.ts))
+- `@deepseek-ai/dsh-session-checkpoint-policy` — requires `llm` · `sessionPersistence` · `sessions` · `tools` ([`packages/session-persistence/session-checkpoint-policy/src/index.ts`](../packages/session-persistence/session-checkpoint-policy/src/index.ts))
 - `@deepseek-ai/dsh-subagent` ([`packages/subagent/subagent/src/index.ts`](../packages/subagent/subagent/src/index.ts))
 - `@deepseek-ai/dsh-tasks` ([`packages/tasks/tasks/src/index.ts`](../packages/tasks/tasks/src/index.ts))
 - `@deepseek-ai/dsh-timeout-policy` — requires `tools` ([`packages/timeout/timeout-policy/src/index.ts`](../packages/timeout/timeout-policy/src/index.ts))
 - `@deepseek-ai/dsh-tool-ask-user` — requires `tools` · `userInteraction` ([`packages/ui/tool-ask-user/src/index.ts`](../packages/ui/tool-ask-user/src/index.ts))
+- `@deepseek-ai/dsh-tool-pty` — requires `pty` · `tools` · `systemPrompt` ([`packages/pty/tool-pty/src/index.ts`](../packages/pty/tool-pty/src/index.ts))
 - `@deepseek-ai/dsh-tool-todo` — requires `tools` ([`packages/todo/tool-todo/src/index.ts`](../packages/todo/tool-todo/src/index.ts))
 - `@deepseek-ai/dsh-user-interaction` ([`packages/ui/user-interaction/src/index.ts`](../packages/ui/user-interaction/src/index.ts))

--- 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:201`](../../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:163`](../../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:172`](../../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:346`](../../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:296`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:315`](../../packages/core/agent/src/types.ts)

 ### `agent/pre-step` — serial

@@ -142,18 +142,21 @@ 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:230`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:246`](../../packages/core/agent/src/types.ts)

 ### `agent/prompt-submit` — waterfall

-Allow, rewrite, or block one claimed prompt before it becomes a user message. Call `next()` for the unchanged default. The signal controls only this turn; listeners may cooperate with it but must not retain it to control another turn.
+Allow, rewrite, or block one claimed prompt before it becomes a user message. Call `next()` for the unchanged default. A listener wrapping a downstream `allow` must preserve its `content` and `additionalContexts` unless it intentionally replaces them. The signal controls only this turn; listeners may cooperate with it but must not retain it to control another turn. Steering messages do not dispatch this event; they join an open turn at a steering checkpoint.

 ```ts cordis-catalog
 /**
 * Allow, rewrite, or block one claimed prompt before it becomes a user
- * message. Call `next()` for the unchanged default. The signal controls only
- * this turn; listeners may cooperate with it but must not retain it to
- * control another turn.
+ * message. Call `next()` for the unchanged default. A listener wrapping a
+ * downstream `allow` must preserve its `content` and `additionalContexts`
+ * unless it intentionally replaces them. The signal controls only this turn;
+ * listeners may cooperate with it but must not retain it to control another
+ * turn. Steering messages do not dispatch this event; they join an open turn
+ * at a steering checkpoint.
 * @param agent - the agent whose turn claimed the message.
 * @param content - the claimed message's blocks, as queued.
 * @param source - the message's resolved source.
@@ -166,7 +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:243`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:262`](../../packages/core/agent/src/types.ts)

 ### `agent/queued` — emit

@@ -178,16 +181,16 @@ Detached, frozen content entered the agent's inbox. Source defaults have already
 * already been applied, so these are the exact values retained for the log.
 * @param agent - the agent whose inbox received the message.
 * @param content - the accepted content blocks retained by the inbox.
- * @param info - the accepted source plus whether it entered as steering.
+ * @param info - the accepted source, contexts, and whether it entered as steering.
 * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
 * @mode emit
 */
-'agent/queued'(this: Scoped<Agent>, agent: Agent, content: ContentBlock[], info: { source: MessageSource; steering: boolean }): void
+'agent/queued'(this: Scoped<Agent>, agent: Agent, content: ContentBlock[], info: { source: MessageSource; contexts: HookContext[]; steering: boolean }): void
 ```

-Types: [Agent](../core-data-structures/core.md) · [ContentBlock](../core-data-structures/core.md) · [MessageSource](../core-data-structures/core.md) · [Scoped](../core-data-structures/scope.md)
+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:191`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:207`](../../packages/core/agent/src/types.ts)

 ### `agent/request` — waterfall

@@ -212,7 +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:257`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:276`](../../packages/core/agent/src/types.ts)

 ### `agent/request-error` — waterfall

@@ -238,7 +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:311`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:330`](../../packages/core/agent/src/types.ts)

 ### `agent/session-prefix` — waterfall

@@ -264,7 +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:272`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:291`](../../packages/core/agent/src/types.ts)

 ### `agent/session-start` — emit

@@ -286,7 +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:214`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:230`](../../packages/core/agent/src/types.ts)

 ### `agent/status` — emit

@@ -306,7 +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:181`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:197`](../../packages/core/agent/src/types.ts)

 ### `agent/step-result` — waterfall

@@ -329,7 +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:284`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:303`](../../packages/core/agent/src/types.ts)

 ### `agent/turn-continuation` — waterfall

@@ -351,7 +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:322`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:341`](../../packages/core/agent/src/types.ts)

 ### `agent/turn-stop` — serial

@@ -373,7 +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:333`](../../packages/core/agent/src/types.ts)
+Source: [`packages/core/agent/src/types.ts:352`](../../packages/core/agent/src/types.ts)

 ## `agent-loop/*`

@@ -569,7 +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:79`](../../packages/core/session/src/index.ts)

 ### `session/disposed` — emit

@@ -590,7 +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:89`](../../packages/core/session/src/index.ts)

 ### `session/event` — emit

@@ -613,7 +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:101`](../../packages/core/session/src/index.ts)

 ### `session/flush` — parallel

@@ -634,7 +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:111`](../../packages/core/session/src/index.ts)

 ## `subagent/*`

--- a/docs/cordis-catalog/services.md
+++ b/docs/cordis-catalog/services.md
@@ -383,7 +383,7 @@ Source: [`packages/ui/commands/src/index.ts:227`](../../packages/ui/commands/src

 ## `ctx.compact` — `CompactService` (abstract seam)

-Abstract compaction service. Implementations own trigger policy, retention, and summarization, and may consume a separate measurement service. A successful run replaces the selected surface span with one summary node and prevents concurrent compaction of the same session. Load one implementation per context as `ctx.compact`.
+Abstract compaction service. Implementations own trigger policy, retention, and summarization, and may consume a separate measurement service. A successful run replaces the selected surface span with one summary node and prevents concurrent compaction of the same session. The replacement user message uses COMPACT_CHECKPOINT_SOURCE so consumers recognize it independently of the backend. Load one implementation per context as `ctx.compact`.

 ```ts cordis-catalog
 /**
@@ -407,6 +407,7 @@ abstract compactIfNeeded( agent: CompactAgentContext, trigger: CompactionTrigger
 * balanced so assistant tool calls remain paired with their results. A model-
 * backed implementation forwards cancellation and rejects active, missing,
 * reversed, or unbalanced ranges. The target session is `agent.session`.
+ * Its replacement user message must use {@link COMPACT_CHECKPOINT_SOURCE}.
 * Use {@link toolPairingBalancedBefore} and {@link toolPairingBalancedAfter}
 * for the edge checks.
 *
@@ -422,7 +423,7 @@ abstract compactRegion( start: number, end: number, agent: CompactAgentContext,

 Types: [CompactionResult](../core-data-structures/compaction.md) · [CompactionTrigger](../core-data-structures/compaction.md)

-Source: [`packages/compact/compact/src/index.ts:39`](../../packages/compact/compact/src/index.ts)
+Source: [`packages/compact/compact/src/index.ts:54`](../../packages/compact/compact/src/index.ts)

 ## `ctx.fs` — `FileSystem` (abstract seam)

@@ -499,12 +500,12 @@ abstract listDir(target: FsTarget, signal?: AbortSignal): Promise<FsDirEntry[]>
 * @param content - the full new file content.
 * @param expected - the write intent guarding the write; omit for unconditional.
 * @param signal - aborts before the atomic rename takes effect.
- * @param sandboxMode - the per-call sandbox mode this write runs under; a
- *   sandboxing backend fences the write by it, the bare backend ignores it.
- *   Omit to leave the backend its own default.
+ * @param sandboxPolicy - the per-call mode and workspace root this write
+ *   runs under; a sandboxing backend fences the write by it, the bare backend
+ *   ignores it. Omit to leave the backend its own default.
 * @returns the outcome, including the version the write produced.
 */
-abstract writeText( target: FsTarget, content: string, expected?: FsWriteIntent, signal?: AbortSignal, sandboxMode?: SandboxMode, ): Promise<FsWriteOutcome>
+abstract writeText( target: FsTarget, content: string, expected?: FsWriteIntent, signal?: AbortSignal, sandboxPolicy?: SandboxExecutionPolicy, ): Promise<FsWriteOutcome>

 /**
 * Atomically edit literal text. When supplied, the version guard is checked
@@ -514,15 +515,15 @@ abstract writeText( target: FsTarget, content: string, expected?: FsWriteIntent,
 * @param edit - the literal search/replace request.
 * @param expected - the version guard; omit for an unconditional edit.
 * @param signal - aborts before the atomic rename takes effect.
- * @param sandboxMode - the per-call sandbox mode this edit runs under; a
- *   sandboxing backend fences the edit by it, the bare backend ignores it.
- *   Omit to leave the backend its own default.
+ * @param sandboxPolicy - the per-call mode and workspace root this edit runs
+ *   under; a sandboxing backend fences the edit by it, the bare backend
+ *   ignores it. Omit to leave the backend its own default.
 * @returns the outcome, including the version the edit produced.
 */
-abstract editText( target: FsTarget, edit: FsEditRequest, expected?: { version: FsVersion }, signal?: AbortSignal, sandboxMode?: SandboxMode, ): Promise<FsEditOutcome>
+abstract editText( target: FsTarget, edit: FsEditRequest, expected?: { version: FsVersion }, signal?: AbortSignal, sandboxPolicy?: SandboxExecutionPolicy, ): Promise<FsEditOutcome>
 ```

-Types: [FsDirEntry](../core-data-structures/filesystem.md) · [FsEditOutcome](../core-data-structures/filesystem.md) · [FsEditRequest](../core-data-structures/filesystem.md) · [FsInfo](../core-data-structures/filesystem.md) · [FsPathInfo](../core-data-structures/filesystem.md) · [FsTarget](../core-data-structures/filesystem.md) · [FsVersion](../core-data-structures/filesystem.md) · [FsWriteIntent](../core-data-structures/filesystem.md) · [FsWriteOutcome](../core-data-structures/filesystem.md) · [SandboxMode](../core-data-structures/sandbox.md)
+Types: [FsDirEntry](../core-data-structures/filesystem.md) · [FsEditOutcome](../core-data-structures/filesystem.md) · [FsEditRequest](../core-data-structures/filesystem.md) · [FsInfo](../core-data-structures/filesystem.md) · [FsPathInfo](../core-data-structures/filesystem.md) · [FsTarget](../core-data-structures/filesystem.md) · [FsVersion](../core-data-structures/filesystem.md) · [FsWriteIntent](../core-data-structures/filesystem.md) · [FsWriteOutcome](../core-data-structures/filesystem.md) · [SandboxExecutionPolicy](../core-data-structures/sandbox.md)

 Source: [`packages/fs/fs/src/index.ts:81`](../../packages/fs/fs/src/index.ts)

@@ -760,6 +761,81 @@ Types: [Agent](../core-data-structures/core.md)

 Source: [`packages/plan/plan-mode/src/index.ts:141`](../../packages/plan/plan-mode/src/index.ts)

+## `ctx.pty` — `PtyService`
+
+In-process registry for replaceable PTY backends and exact-Agent sessions.
+
+```ts cordis-catalog
+/**
+ * Register one backend type for this effect scope.
+ * @param backend - provider with a non-empty unique type.
+ * @returns disposer that removes exactly this contribution.
+ */
+registerBackend(backend: PtyBackend): () => void
+
+/**
+ * List registered backend types in registration order.
+ * @returns fresh backend type names.
+ */
+listBackends(): string[]
+
+/**
+ * Create and publish one owner-scoped session after backend setup succeeds.
+ * @param owner - exact registered Agent that owns access and cleanup.
+ * @param request - backend type plus optional owner-local name and cwd.
+ * @param signal - cancellation of unpublished setup.
+ * @returns published identity, metadata, status, and MOTD.
+ */
+async spawn(owner: Agent, request: PtySpawnRequest, signal?: AbortSignal): Promise<PtySpawnResult>
+
+/**
+ * Start one exclusive interactive send.
+ * @param owner - exact session owner.
+ * @param id - target PTY identity.
+ * @param request - explicit text, submit behavior, and cancellation.
+ * @returns live operation handle for foreground await or task registration.
+ */
+startSend(owner: Agent, id: PtySessionId, request: PtySendRequest): PtySendOperation
+
+/**
+ * Read one bounded scrollback page from an owned session.
+ * @param owner - exact session owner.
+ * @param id - target PTY identity.
+ * @param request - optional newest-relative offset and line count.
+ * @returns bounded retained text and pagination metadata.
+ */
+read(owner: Agent, id: PtySessionId, request: PtyReadRequest = {}): PtyReadResult
+
+/**
+ * Deliver an allowed signal through an owned backend session.
+ * @param owner - exact session owner.
+ * @param id - target PTY identity.
+ * @param signal - allowed POSIX signal name.
+ * @returns delivered foreground process-group identity.
+ */
+signal(owner: Agent, id: PtySessionId, signal: PtySignal): Promise<PtySignalResult>
+
+/**
+ * Close one owned session and remove it only after quiescent backend cleanup.
+ * @param owner - exact session owner.
+ * @param id - target PTY identity.
+ * @param reason - diagnostic cleanup reason.
+ * @returns true for a newly closed session, false when the same close is already in flight.
+ */
+async kill(owner: Agent, id: PtySessionId, reason = 'model request'): Promise<boolean>
+
+/**
+ * List fresh snapshots for exactly one owner.
+ * @param owner - exact owner whose sessions are visible.
+ * @returns owner-visible snapshots in publication order.
+ */
+list(owner: Agent): PtySessionSnapshot[]
+```
+
+Types: [Agent](../core-data-structures/core.md) · [PtyBackend](../core-data-structures/pty.md) · [PtyReadRequest](../core-data-structures/pty.md) · [PtyReadResult](../core-data-structures/pty.md) · [PtySendOperation](../core-data-structures/pty.md) · [PtySendRequest](../core-data-structures/pty.md) · [PtySessionId](../core-data-structures/pty.md) · [PtySessionSnapshot](../core-data-structures/pty.md) · [PtySignal](../core-data-structures/pty.md) · [PtySignalResult](../core-data-structures/pty.md) · [PtySpawnRequest](../core-data-structures/pty.md) · [PtySpawnResult](../core-data-structures/pty.md)
+
+Source: [`packages/pty/pty/src/index.ts:95`](../../packages/pty/pty/src/index.ts)
+
 ## `ctx.sandbox` — `SandboxProvider` (abstract seam)

 Abstract process-sandbox service. confine must return enforcing argv or fail closed at wrap or runner-execution time; silent unconfined passthrough is forbidden. Functional probes arbitrate multi-runner chains and may be skipped for a sole candidate, whose own refusal remains the fail-closed end.
@@ -781,13 +857,28 @@ abstract confine(argv: readonly string[], policy: SandboxPolicy): ConfinedArgv

 Types: [ConfinedArgv](../core-data-structures/sandbox.md) · [SandboxPolicy](../core-data-structures/sandbox.md)

-Source: [`packages/sandbox/sandbox/src/index.ts:122`](../../packages/sandbox/sandbox/src/index.ts)
+Source: [`packages/sandbox/sandbox/src/index.ts:131`](../../packages/sandbox/sandbox/src/index.ts)

 ## `ctx.sandboxPolicy` — `SandboxPolicyService`

-The sandbox-policy service (`ctx.sandboxPolicy`). Owns the deployment default mode and workspace root; enforcing implementations read defaultMode and workspaceRoot, and the tool layers fold each session's `sandbox/mode` override with effectiveSandboxMode on top.
+The sandbox-policy service (`ctx.sandboxPolicy`). Owns the deployment default mode and fallback workspace root. Tool layers call resolve for each execution so a session's mode log and immutable cwd travel together to every enforcing capability.

-Source: [`packages/sandbox/sandbox-policy/src/index.ts:60`](../../packages/sandbox/sandbox-policy/src/index.ts)
+```ts cordis-catalog
+/**
+ * Resolve the complete policy for one capability call. An approved explicit
+ * mode outranks the session's last `sandbox/mode` event, which outranks the
+ * deployment default. A session cwd is its workspace-write boundary; the
+ * configured root is the fallback for agentless calls and sessions without a
+ * cwd.
+ * @param request - optional session and approved mode override.
+ * @returns the fully resolved per-call mode and absolute workspace root.
+ */
+resolve(request: SandboxPolicyRequest = {}): SandboxExecutionPolicy
+```
+
+Types: [SandboxExecutionPolicy](../core-data-structures/sandbox.md) · [SandboxPolicyRequest](../core-data-structures/sandbox.md)
+
+Source: [`packages/sandbox/sandbox-policy/src/index.ts:68`](../../packages/sandbox/sandbox-policy/src/index.ts)

 ## `ctx.sessionPersistence` — `SessionPersistence` (abstract seam)

@@ -869,6 +960,14 @@ async readTitle(sessionId: SessionId): Promise<SessionTitleSnapshot | undefined>
 */
 async listEvents(sessionId: SessionId): Promise<SessionEventRecord[]>

+/**
+ * Read one session's complete current model surface from one corpus observation.
+ * @param sessionId - live-preferred session id to read.
+ * @returns cloned header, current surface, and raw-log capture boundary.
+ * @throws when source resolution fails or the session surface is invalid.
+ */
+async readSurface(sessionId: SessionId): Promise<SessionSurfaceSnapshot>
+
 /**
 * Trace known ancestry and descendants from one corpus observation.
 * @param sessionId - logical session id to trace.
@@ -893,9 +992,39 @@ async traceEvent(request: SessionEventTraceRequest): Promise<SessionEventTrace>
 async readEvent(request: SessionEventReadRequest): Promise<SessionEventWindow>
 ```

-Types: [SessionEventReadRequest](../core-data-structures/session-query.md) · [SessionEventRecord](../core-data-structures/session-query.md) · [SessionEventTrace](../core-data-structures/session-query.md) · [SessionEventTraceRequest](../core-data-structures/session-query.md) · [SessionEventWindow](../core-data-structures/session-query.md) · [SessionId](../core-data-structures/core.md) · [SessionLineageTrace](../core-data-structures/session-query.md) · [SessionRecord](../core-data-structures/session-query.md) · [SessionTitleSnapshot](../core-data-structures/session-title.md)
+Types: [SessionEventReadRequest](../core-data-structures/session-query.md) · [SessionEventRecord](../core-data-structures/session-query.md) · [SessionEventTrace](../core-data-structures/session-query.md) · [SessionEventTraceRequest](../core-data-structures/session-query.md) · [SessionEventWindow](../core-data-structures/session-query.md) · [SessionId](../core-data-structures/core.md) · [SessionLineageTrace](../core-data-structures/session-query.md) · [SessionRecord](../core-data-structures/session-query.md) · [SessionSurfaceSnapshot](../core-data-structures/session-query.md) · [SessionTitleSnapshot](../core-data-structures/session-title.md)

-Source: [`packages/session-query/session-query/src/index.ts:40`](../../packages/session-query/session-query/src/index.ts)
+Source: [`packages/session-query/session-query/src/index.ts:41`](../../packages/session-query/session-query/src/index.ts)
+
+## `ctx.sessionReferences` — `SessionReferenceService`
+
+Exact-read consumer that prepares immutable cross-session message context.
+
+```ts cordis-catalog
+/**
+ * List reference candidates, ranked by working-directory affinity.
+ * @param agent - target agent; self is excluded and its cwd drives ranking.
+ * @param query - optional case-insensitive session-id/cwd substring.
+ * @param limit - optional positive result cap.
+ * @param signal - optional cancellation boundary for host autocomplete teardown.
+ * @returns candidates labeled by latest title or, when absent, session id.
+ */
+async listCandidates( agent: Agent, query = '', limit = this.config.candidateLimit, signal?: AbortSignal, ): Promise<SessionReferenceCandidate[]>
+
+/**
+ * Snapshot all references before enqueue and return one aggregated durable context.
+ * @param agent - target agent; references to it are rejected.
+ * @param content - already host-normalized readable message content.
+ * @param references - structured source sessions in mention order.
+ * @param signal - optional cancellation boundary for host request teardown.
+ * @returns detached content and zero or one prepared contexts.
+ */
+async prepare( agent: Agent, content: ContentBlock[], references: SessionReferenceInput[], signal?: AbortSignal, ): Promise<PreparedReferencedMessage>
+```
+
+Types: [Agent](../core-data-structures/core.md) · [ContentBlock](../core-data-structures/core.md) · [PreparedReferencedMessage](../core-data-structures/session-reference.md) · [SessionReferenceCandidate](../core-data-structures/session-reference.md) · [SessionReferenceInput](../core-data-structures/session-reference.md)
+
+Source: [`packages/context/session-reference/src/index.ts:69`](../../packages/context/session-reference/src/index.ts)

 ## `ctx.sessions` — `SessionStore`

@@ -1044,7 +1173,7 @@ 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:605`](../../packages/core/session/src/index.ts)

 ## `ctx.sessionTitle` — `SessionTitleService`

@@ -1078,7 +1207,7 @@ 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`

--- a/docs/core-data-structures/bash.md
+++ b/docs/core-data-structures/bash.md
@@ -67,8 +67,8 @@ interface BashExecRequest {
   * reject non-`DSH_*` names supplied through this managed channel.
   */
  dshEnv?: DshEnvironment | undefined
-  /** Explicit per-call sandbox mode override. */
-  sandboxMode?: SandboxMode | undefined
+  /** Fully resolved per-call sandbox policy; sandboxing executors default it. */
+  sandboxPolicy?: SandboxExecutionPolicy | undefined
 }
 ```

@@ -100,8 +100,8 @@ interface BashExecSpec {
  env?: Record<string, string> | undefined
  /** Managed `DSH_*` snapshot; implementations reject ordinary names. */
  dshEnv?: DshEnvironment | undefined
-  /** Resolved sandbox mode; ignored by executors that do not confine. */
-  sandboxMode: SandboxMode | undefined
+  /** Resolved sandbox policy; ignored by executors that do not confine. */
+  sandboxPolicy: SandboxExecutionPolicy | undefined
 }
 ```

@@ -159,7 +159,7 @@ interface CollectedOutput {

 ## File sandbox: `BashSandboxInfo`

-A sandbox-consuming executor exposes its configured fallback through `BashExecutor.sandboxMode`. The tool layer folds each session's durable `sandbox/mode` override (owned by [`@deepseek-ai/dsh-sandbox-policy`](../../packages/sandbox/sandbox-policy/README.md)) and may replace it for one user-approved strictly wider call. The mode/enforcement vocabulary is owned by the [`@deepseek-ai/dsh-sandbox` seam](sandbox.md); modes govern file effects only.
+A sandbox-consuming executor exposes its configured mode fallback through `BashExecutor.sandboxMode`. The tool layer asks [`@deepseek-ai/dsh-sandbox-policy`](../../packages/sandbox/sandbox-policy/README.md) to resolve each calling session's durable `sandbox/mode` override and immutable cwd into `BashExecRequest.sandboxPolicy`; a user-approved strictly wider call replaces only the mode. The mode/root/enforcement vocabulary is owned by the [`@deepseek-ai/dsh-sandbox` seam](sandbox.md); modes govern file effects only.

 A sandboxed run reports its mode, conservative denial classification, and enforcement completeness. `runnerFailed` marks a sandbox runner failure before the command ran; foreground execution throws `SANDBOX_UNAVAILABLE`, while a settled background process has only its facts channel.

--- a/docs/core-data-structures/compaction.md
+++ b/docs/core-data-structures/compaction.md
@@ -58,7 +58,7 @@ Automatic callers state why policy is running; implementations may treat confirm
 type CompactionTrigger = 'pressure' | 'context-overflow'
 ```

-`CompactService` exposes `compactIfNeeded(agent, trigger, signal)` for automatic `pressure` or `context-overflow` policy, returning `null` when no safe work exists, and `compactRegion(...)` for an explicit inclusive surface range. Implementations must forward the supplied signal to summarization. The seam owns no pricing API: the singleton [`ctx.tokenMeter`](token-meter.md) directly owns estimation and replay, while `dsh-compact-basic` owns retention, event sequencing, routed summarization calls, and their configuration.
+`CompactService` exposes `compactIfNeeded(agent, trigger, signal)` for automatic `pressure` or `context-overflow` policy, returning `null` when no safe work exists, and `compactRegion(...)` for an explicit inclusive surface range. Every backend marks its replacement `user/message` with the package-exported `COMPACT_CHECKPOINT_SOURCE`; consumers call `isCompactCheckpointSource()` instead of coupling checkpoint recognition to one backend. Implementations must forward the supplied signal to summarization. The seam owns no pricing API: the singleton [`ctx.tokenMeter`](token-meter.md) directly owns estimation and replay, while `dsh-compact-basic` owns retention, event sequencing, routed summarization calls, and their configuration.

 Pressure compaction runs at serial `agent/post-step`, after successful assistant output, tool results, buffered context, and steering are durable but before `step/end`. Once pressure or canonical overflow qualifies, compact-basic invokes optional [`ctx.toolResultPrune`](../../packages/compact/compact-tool-result-prune/README.md) before range selection, remeasures through `ctx.tokenMeter`, and can advance the surface without a summary. Failed-request recovery runs through `agent/request-error` after the failed step closes and authorizes a fresh numbered-step retry only when the surface replacement generation advances, even if later summary work throws after pruning; cancellation still wins. Region boundaries preserve tool-call/result pairing but not whole turns, allowing early closed steps of one oversized turn to compact. `dsh-compact-basic` owns thresholds, retained-tail policy, overflow caps, and failure handling.

--- a/docs/core-data-structures/core.md
+++ b/docs/core-data-structures/core.md
@@ -29,7 +29,8 @@ Everything else is documented on a **sub-page**, not here. The rule that draws t
 | [user-interaction.md](user-interaction.md) | the UI-backed human question/answer seam: `AskUserQuestionRequest`, answer/options vocabulary, provider API, error taxonomy |
 | [approval.md](approval.md) | the one-shot user-approval seam: `ApprovalRequest`, `ApprovalOutcome`, per-session policy, audit and answerer contracts |
 | [bash.md](bash.md) | the bash executor seam: `BashExecRequest`/`Spec`, `BashRunResult`, background `BashProcess` handles |
-| [sandbox.md](sandbox.md) | the process-confinement seam: file-effect modes, `SandboxPolicy`, `ConfinedArgv`, enforcement and fail-closed errors |
+| [pty.md](pty.md) | persistent terminal ids, backend/session contracts, send readiness, bounded reads, and owner-visible snapshots |
+| [sandbox.md](sandbox.md) | per-session policy resolution and the process-confinement seam: file-effect modes, execution/provider policies, `ConfinedArgv`, enforcement and fail-closed errors |
 | [code-runtime.md](code-runtime.md) | the code-execution seam: `CodeRunRequest`/`Result`, binding namespaces, captured logs, the `CodeRunFailure` taxonomy |
 | [filesystem.md](filesystem.md) | the filesystem seam: `FsTarget`, read/write/edit outcomes, observed-file state, `FsErrorCode` |
 | [lsp.md](lsp.md) | the LSP navigation seam: `LspQueryRequest`/`Result`, `LspProvider`/`Service`, four operations, `LspError` |
@@ -358,11 +359,27 @@ The fourteen event variants (`turn/start`, `turn/end`, `step/start`, `step/end`,

 Source: [`packages/core/agent/src/types.ts`](../../packages/core/agent/src/types.ts)

-`InjectOptions` extends ordinary message attribution with durable model-hidden JSON metadata:
+```ts type-equiv
+/**
+ * Message options. An omitted source attests direct human input as `{ kind: 'user' }`
+ * and may authorize policy consumers, so non-human producers must label their content.
+ */
+interface SendOptions {
+  source?: MessageSource
+  /**
+   * Model-facing contexts captured with this inbox item. A queued prompt exposes
+   * them through the default `agent/prompt-submit` allow decision, while steering
+   * records them directly at its next checkpoint.
+   */
+  contexts?: HookContext[]
+}
+```
+
+`InjectOptions` accepts ordinary message attribution and durable model-hidden JSON metadata. Attached contexts belong only to queued or steering input, so synthetic injection cannot accept them:

 ```ts type-equiv
 /** Options specific to durable synthetic context injection. */
-interface InjectOptions extends SendOptions {
+interface InjectOptions extends Omit<SendOptions, 'contexts'> {
  /** Opaque JSON state retained in the session event but hidden from the model. */
  meta?: JsonValue
 }
@@ -390,7 +407,8 @@ interface Agent {
   * Queue one detached, frozen lossless-JSON item. If claimed, it is the sole
   * ordinary message in its FIFO-ordered turn; the next claimed item waits for
   * that turn's checkpoint.
-   * Invalid input throws synchronously before notification or enqueue.
+   * Attached contexts share the same snapshot and ownership boundary. Invalid
+   * input throws synchronously before notification or enqueue.
   */
  send(content: ContentBlock[], options?: SendOptions): void

@@ -442,15 +460,21 @@ 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)

 ```ts type-equiv
-/** Model-facing context injected by a listener; `source` prevents plugin text from being labeled as user input. */
+/** Model-facing context injected by a listener or atomically attached to one inbox message. */
 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
 }
@@ -460,10 +484,13 @@ 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.
+ * 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[] }
--- a/docs/core-data-structures/pty.md
+++ b/docs/core-data-structures/pty.md
@@ -0,0 +1,89 @@
+# Persistent PTY Sessions
+
+Types shared by PTY backends, `ctx.pty`, and the model-facing consumer. The [persistent PTY Agent Note](../../.agents/notes/implemented/feature/2026-07-16-persistent-pty-sessions.md) owns the rationale; this page records the cross-package vocabulary from [`packages/pty/pty/src/types.ts`](../../packages/pty/pty/src/types.ts).
+
+## Identity and readiness
+
+`PtySessionId` is a service-minted branded id. Optional names are owner-local display metadata; authorization compares the exact owning `Agent`, not a name or guessed id.
+
+`PtyWaitReason` says why one send returned. It is independent from `PtySessionStatus`: silence or timeout may return while the top-level shell remains alive, while `session_exit` means that shell exited rather than an arbitrary foreground child.
+
+```ts type-equiv
+/** Why one interactive send returned control to its caller. */
+type PtyWaitReason = 'stdin_read' | 'inferred_idle' | 'timeout' | 'session_exit'
+```
+
+```ts type-equiv
+/** Top-level PTY process status, independent of a send's wait reason. */
+type PtySessionStatus =
+  | { kind: 'running' }
+  | { kind: 'exited'; exitCode: number | null; signal: NodeJS.Signals | null }
+```
+
+## Backend and live session
+
+A backend owns how one registered type starts and detects readiness. `PtyService` publishes the returned session only after setup succeeds, then owns id authorization and cleanup. A backend session owns terminal state and captured-resource quiescence.
+
+```ts type-equiv
+/** Replaceable provider for one PTY session type. */
+interface PtyBackend {
+  /** Stable type selected by {@link PtySpawnRequest.type}. */
+  readonly type: string
+  /** Create an unpublished session or reject after cleaning partial resources. */
+  spawn(spec: PtyBackendSpawnSpec): Promise<PtyBackendSession>
+}
+```
+
+```ts type-equiv
+/** Backend-owned live session retained by {@link PtyService}. */
+interface PtyBackendSession {
+  /** Initial bounded terminal output returned from `terminal_open`. */
+  readonly motd: string
+  /** Top-level process id when one exists. */
+  readonly pid?: number
+  /** Start one exclusive send operation. */
+  startSend(request: PtySendRequest): PtySendOperation
+  /** Read one bounded page from retained scrollback. */
+  read(request: PtyReadRequest): PtyReadResult
+  /** Signal the verified foreground process group. */
+  signal(signal: PtySignal): Promise<PtySignalResult>
+  /** Observe top-level process status. */
+  status(): PtySessionStatus
+  /** Idempotently close the captured owned process tree and await quiescence. */
+  close(reason: string): Promise<void>
+}
+```
+
+## Send and retained output
+
+One live session accepts one active send. Its operation exposes a consuming output cursor for generic background tasks and one terminal result for a foreground caller. `PtyReadResult` separately pages the bounded session scrollback.
+
+```ts type-equiv
+/** Live backend-owned send; exactly one may be active per PTY session. */
+interface PtySendOperation {
+  /** Resolves after readiness, timeout, cancellation, or top-level process exit. */
+  done: Promise<PtySendResult>
+  /** Consume output produced since the prior call. */
+  readOutput(): PtySendRead
+  /** Request `SIGINT`; returns false after the operation settled. */
+  cancel(): boolean
+}
+```
+
+```ts type-equiv
+/** Settled result for one foreground or background send. */
+interface PtySendResult {
+  /** Bounded rendered terminal delta remaining at settlement. */
+  viewport: string
+  /** Why the wait returned; this does not imply arbitrary child-process exit. */
+  waitReason: PtyWaitReason
+  /** Top-level session status observed at settlement. */
+  sessionStatus: PtySessionStatus
+  /** Whether output was dropped from the operation or retained scrollback. */
+  truncated: boolean
+}
+```
+
+## Ownership and durability
+
+`PtyService` attaches one awaited cleanup to the exact owner scope, rejects foreign operations, and keeps sessions alive across backend or tool-plugin reload. PTY state and raw bytes remain process-local. Model input and bounded returned output are durable through the existing `tool/call`, `tool/result`, and task-result paths rather than duplicate PTY session events.
--- a/docs/core-data-structures/sandbox.md
+++ b/docs/core-data-structures/sandbox.md
@@ -38,7 +38,35 @@ type SandboxEnforcement = 'full' | 'partial'

 ## Per-call policy

-The policy is fully resolved and carried per call. This permits concurrent consumers and one-shot escalated retries to ask the same provider for different boundaries without mutating provider state.
+The complete execution policy is resolved and carried per capability call. It includes `danger-full-access` so a consumer can resolve policy once before deciding whether to bypass confinement. Normal tool calls derive `workspaceRoot` from the calling session's immutable cwd; deployment configuration is the agentless fallback. The root is canonicalized with filesystem semantics before lexical normalization, so a cwd containing `symlink/..` identifies the directory where a spawned process actually runs.
+
+```ts type-equiv
+/**
+ * The complete file-effect policy resolved for one capability call. The root
+ * is carried even under modes that do not consume it so callers can resolve
+ * policy once before choosing the enforcement path.
+ */
+interface SandboxExecutionPolicy {
+  /** The file-effect mode this execution runs under. */
+  mode: SandboxMode
+  /** Absolute root directory `workspace-write` may write under. */
+  workspaceRoot: string
+}
+```
+
+`ctx.sandboxPolicy.resolve()` accepts the active session and, for an approved retry, an explicit mode. The service owns precedence and root fallback so bash and fs do not repeat it.
+
+```ts type-equiv
+/** Inputs that select the sandbox policy for one capability call. */
+interface SandboxPolicyRequest {
+  /** Calling session; its immutable cwd becomes the workspace boundary. */
+  session?: Session
+  /** Explicit approved mode override, which outranks session policy. */
+  mode?: SandboxMode
+}
+```
+
+Only a confined execution reaches `ctx.sandbox`; its provider policy narrows the mode while retaining the same root. This permits concurrent sessions, consumers, and one-shot escalated retries to ask the same provider for different boundaries without mutating provider state.

 ```ts type-equiv
 /**
@@ -46,15 +74,12 @@ The policy is fully resolved and carried per call. This permits concurrent consu
 * fixed on the provider: two consumers may confine under different policies
 * at the same instant (bash under `read-only` while a confined child agent
 * needs its state directory writable), and an approved escalated retry is a
- * new call with a wider policy. Defaulting/resolution is the consumer's
- * explicit step (its config owns the fallback chain); the provider treats
- * the policy as fully specified.
+ * new call with a wider policy. Defaulting/resolution is an explicit step at
+ * the consumer boundary; the provider treats the policy as fully specified.
 */
-interface SandboxPolicy {
+interface SandboxPolicy extends SandboxExecutionPolicy {
  /** The file-effect mode this execution runs under. */
  mode: ConfinedSandboxMode
-  /** Absolute root directory `workspace-write` may write under. */
-  workspaceRoot: string
 }
 ```

--- a/docs/core-data-structures/session-query.md
+++ b/docs/core-data-structures/session-query.md
@@ -25,6 +25,20 @@ interface SessionRecord {
 }
 ```

+`SessionSurfaceSnapshot` is one exact-read observation rather than a retained subscription. Its raw-log boundary and folded events come from the same live-preferred load.
+
+```ts type-equiv
+/** One atomic live-preferred observation of a session's current model surface. */
+interface SessionSurfaceSnapshot {
+  /** Cloned session header selected from the same corpus observation as `events`. */
+  session: SessionHeader
+  /** Highest raw-log seq included in the observation, or `null` for an empty log. */
+  capturedThroughSeq: number | null
+  /** Cloned current surface events in model-history order. */
+  events: SurfaceEvent[]
+}
+```
+
 ```ts type-equiv
 /** Lightweight metadata for one event within a logical session. */
 interface SessionEventRecord {
--- a/docs/core-data-structures/session-reference.md
+++ b/docs/core-data-structures/session-reference.md
@@ -0,0 +1,65 @@
+# Session References
+
+Structured cross-session reference requests and prepared message contexts. The [package contract](../../packages/context/session-reference) owns canonical URIs, current-surface projection, tag-safe JSON and byte retention, stable errors, and the untrusted model prompt. Host adapters use these types instead of passing their UI mention syntax into the agent core.
+
+Source: [`packages/context/session-reference/src/types.ts`](../../packages/context/session-reference/src/types.ts)
+
+## Inputs and candidates
+
+`SessionReferenceInput` is the host-independent selection. The id is authoritative; the label is display metadata carried into the snapshot.
+
+```ts type-equiv
+/** One source session selected by a host. */
+interface SessionReferenceInput {
+  /** Opaque source session identity. */
+  sessionId: SessionId
+  /** Optional user-facing mention label. */
+  label?: string
+}
+```
+
+`SessionReferenceCandidate` is host-facing discovery output. Its label uses the latest session title when present, while filtering still searches only session id and cwd and never transcript text.
+
+```ts type-equiv
+/** One host-facing candidate from exact session metadata. */
+interface SessionReferenceCandidate {
+  /** Opaque source session identity. */
+  sessionId: SessionId
+  /** Latest log-backed title, falling back to the opaque session id. */
+  label: string
+  /** Source session working directory, when recorded. */
+  cwd?: string
+  /** Source session creation time in Unix epoch milliseconds. */
+  createdAt: number
+}
+```
+
+## Prepared messages
+
+Preparation preserves readable current-message content and returns at most one aggregated context. The host binds `contexts` to that exact `send()` or `steer()` call.
+
+```ts type-equiv
+/** Message payload and the zero-or-one durable snapshot contexts bound to it. */
+interface PreparedReferencedMessage {
+  /** Readable message content after host mention tokens are removed. */
+  content: ContentBlock[]
+  /** Empty without references; otherwise one aggregated untrusted context. */
+  contexts: HookContext[]
+}
+```
+
+## Errors
+
+`SessionReferenceError.code` separates invalid configuration or input, self-reference, count limits, source-read failure, budget failure, and cancellation. Host protocols map these codes to their own error envelopes without inspecting prompt bytes.
+
+```ts type-equiv
+/** Stable failure codes exposed to host adapters. */
+type SessionReferenceErrorCode =
+  | 'SESSION_REFERENCE_INVALID_CONFIG'
+  | 'SESSION_REFERENCE_INVALID_REFERENCE'
+  | 'SESSION_REFERENCE_SELF_REFERENCE'
+  | 'SESSION_REFERENCE_TOO_MANY'
+  | 'SESSION_REFERENCE_READ_FAILED'
+  | 'SESSION_REFERENCE_BUDGET_EXCEEDED'
+  | 'SESSION_REFERENCE_CANCELLED'
+```
--- 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.

@@ -528,6 +542,6 @@ The hook bridges' `hook/invoked` / `hook/result` provenance pairs (from `@deepse

 ## Durability contract

-What a persistence backend relies on: the durable log persists every event verbatim, **including** `assistant/chunk` — `seq` must stay contiguous, so chunks cannot be filtered out of the canonical log. All `event.data` must be JSON-serializable; `Session.append` enforces this at the source (throwing on non-serializable data), so a bad event never enters the log and `session.events` always equals what a backend can persist. Adding an event type that carries non-serializable data, or that breaks the turn/step nesting checked by the session invariant companion, is a breaking change to the on-disk format.
+What a persistence backend relies on: the durable log persists every event losslessly, **including** `assistant/chunk` — `seq` must stay contiguous, so chunks cannot be filtered out of the canonical log. A backend may choose its own storage encoding for an event batch as long as `load` returns the exact appended events (the JSONL backend's opt-in packed chunk rows are such an encoding — see [persistence.md](persistence.md)). All `event.data` must be JSON-serializable; `Session.append` enforces this at the source (throwing on non-serializable data), so a bad event never enters the log and `session.events` always equals what a backend can persist. Adding an event type that carries non-serializable data, or that breaks the turn/step nesting checked by the session invariant companion, is a breaking change to the on-disk format.

 The backends that consume this contract are on [persistence.md](persistence.md).
--- a/docs/development.i18n.yaml
+++ b/docs/development.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
-development.md: 10406cebae1bf83fff663903b1478c9acb8476a1
-development.zh.md: 50051ffd631518b37c3ad96f5fd3830cf6893ec9
+development.md: 3559b09d86395707f222aad0a281c9db1246c24f
+development.zh.md: 8664a3291c04a5338fdadbce8f24b160cc9ec0a8
--- a/docs/development.md
+++ b/docs/development.md
@@ -65,6 +65,8 @@ The vendor manifest guard checks that changes under `vendor/*/src` are staged wi

 The hooks intentionally do not run tests, snapshots, documentation checks, builds, or hygiene. Contributors run the [checks relevant to the changed behavior](../AGENTS.md#run-relevant-checks-locally) once; CI owns exhaustive coverage, built-artifact smokes, and the Node 22.19, 24, and 26 compatibility matrix.

+Contributors can opt into the comprehensive local gate set with `pnpm run check:all`. The command is independent of both Git hooks and is not an agent instruction.
+
 ## CI gates

 The keyless [CI workflow](../.github/workflows/ci.yml) groups independent gates into broad lanes and runs a smaller compatibility signal across supported Node versions. Artifact consumers wait for one build within their lane. The separate real-API workflow runs `pnpm run test:e2e` with its configured worker bound. See [scripts/run-gates.ts](../scripts/run-gates.ts) and the workflow files for the current gate and job inventory.
@@ -77,6 +79,7 @@ Use these from the repo root:
 pnpm run test           # unit tests
 pnpm run test:coverage  # unit tests with per-file coverage gates
 pnpm run test:e2e       # real-API tests; self-skips without DEEPSEEK_API_KEY
+pnpm run check:all      # comprehensive opt-in gate set; not wired to Git hooks
 pnpm run typecheck      # build package/vendor outputs, then typecheck examples, tests, and scripts
 pnpm run lint           # eslint .
 pnpm run lint:fix       # eslint . --fix
--- a/docs/development.zh.md
+++ b/docs/development.zh.md
@@ -65,6 +65,8 @@ vendor manifest 守卫检查 `vendor/*/src` 下的改动是否连同对应的 `v

 这些钩子有意不运行测试、快照、文档检查、构建或 `hygiene`。贡献者只运行一次[与改动行为相关的检查](../AGENTS.md#run-relevant-checks-locally)；CI 负责全量覆盖率门禁、构建产物冒烟测试，以及 Node 22.19、24 和 26 兼容性矩阵。

+贡献者可以选择运行 `pnpm run check:all`，执行全面的本地门禁集。该命令独立于两个 Git 钩子，也不是对 agent 的指令。
+
 ## CI 门禁

 keyless [CI 工作流](../.github/workflows/ci.yml) 将独立门禁分组到若干宽粒度 lane，并在受支持的 Node 版本上运行一组较小的兼容性检查。产物消费方在各自 lane 内等待一次 build。单独的真实 API 工作流按其配置的 worker 上限运行 `pnpm run test:e2e`。当前门禁和 job 清单以 [scripts/run-gates.ts](../scripts/run-gates.ts) 和工作流文件为准。
@@ -77,6 +79,7 @@ keyless [CI 工作流](../.github/workflows/ci.yml) 将独立门禁分组到若
 pnpm run test           # unit tests
 pnpm run test:coverage  # unit tests with per-file coverage gates
 pnpm run test:e2e       # real-API tests; self-skips without DEEPSEEK_API_KEY
+pnpm run check:all      # comprehensive opt-in gate set; not wired to Git hooks
 pnpm run typecheck      # build package/vendor outputs, then typecheck examples, tests, and scripts
 pnpm run lint           # eslint .
 pnpm run lint:fix       # eslint . --fix
--- a/docs/event-producer-consumer.md
+++ b/docs/event-producer-consumer.md
@@ -8,33 +8,33 @@ 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:201`](../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:163`](../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:172`](../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:346`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`goal-session`](../packages/goal/goal-session), `runtime`, [`tui`](../packages/ui/tui) |
-| `agent/post-step` | `serial` | [`packages/core/agent/src/types.ts:296`](../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:230`](../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:243`](../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), [`plan-mode`](../packages/plan/plan-mode), [`repeat-tool-guard`](../packages/guard/repeat-tool-guard) |
-| `agent/queued` | `emit` | [`packages/core/agent/src/types.ts:191`](../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:257`](../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:311`](../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), [`plan-mode`](../packages/plan/plan-mode) |
-| `agent/session-prefix` | `waterfall` | [`packages/core/agent/src/types.ts:272`](../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:214`](../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:181`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`emit`) | [`agent`](../packages/core/agent), [`goal-session`](../packages/goal/goal-session), `runtime`, [`tui`](../packages/ui/tui) |
-| `agent/step-result` | `waterfall` | [`packages/core/agent/src/types.ts:284`](../packages/core/agent/src/types.ts) | [`agent-loop`](../packages/core/agent-loop) (`waterfall`) | - |
-| `agent/turn-continuation` | `waterfall` | [`packages/core/agent/src/types.ts:322`](../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), [`plan-mode`](../packages/plan/plan-mode) |
-| `agent/turn-stop` | `serial` | [`packages/core/agent/src/types.ts:333`](../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), `runtime`, [`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), [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy) |
+| `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), [`plan-mode`](../packages/plan/plan-mode), [`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), [`tui`](../packages/ui/tui) |
+| `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), [`plan-mode`](../packages/plan/plan-mode) |
+| `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), `runtime`, [`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), [`plan-mode`](../packages/plan/plan-mode) |
+| `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:30`](../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:103`](../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) |
 | `fs/observed` | `emit` | [`packages/fs/fs/src/index.ts:71`](../packages/fs/fs/src/index.ts) | [`tool-fs`](../packages/fs/tool-fs) (`emit`) | [`fs-policy`](../packages/fs/fs-policy) |
 | `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), `runtime`, [`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), `runtime`, [`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), `runtime`, [`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) |
+| `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-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy), [`session-title`](../packages/session-title/session-title) |
+| `session/created` | `emit` | [`packages/core/session/src/index.ts:79`](../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), `runtime`, [`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:89`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`agent-loop`](../packages/core/agent-loop), `runtime`, [`session-persistence`](../packages/session-persistence/session-persistence), [`session-title`](../packages/session-title/session-title) |
+| `session/event` | `emit` | [`packages/core/session/src/index.ts:101`](../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), `runtime`, [`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:111`](../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) |
@@ -42,7 +42,7 @@ This matrix shows which packages dispatch each harness-owned event and which pac
 | `system-prompt/assemble` | `waterfall` | [`packages/core/system-prompt/src/index.ts:29`](../packages/core/system-prompt/src/index.ts) | [`system-prompt`](../packages/core/system-prompt) (`waterfall`) | [`agent`](../packages/core/agent), [`system-prompt`](../packages/core/system-prompt) |
 | `system-prompt/change` | `emit` | [`packages/core/system-prompt/src/index.ts:35`](../packages/core/system-prompt/src/index.ts) | [`system-prompt`](../packages/core/system-prompt) (`emit`) | - |
 | `tools/change` | `emit` | [`packages/core/tools/src/index.ts:123`](../packages/core/tools/src/index.ts) | [`tools`](../packages/core/tools) (`emit`) | - |
-| `tools/execute` | `waterfall` | [`packages/core/tools/src/index.ts:93`](../packages/core/tools/src/index.ts) | [`tools`](../packages/core/tools) (`waterfall`) | [`timeout-policy`](../packages/timeout/timeout-policy) |
+| `tools/execute` | `waterfall` | [`packages/core/tools/src/index.ts:93`](../packages/core/tools/src/index.ts) | [`tools`](../packages/core/tools) (`waterfall`) | [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy), [`timeout-policy`](../packages/timeout/timeout-policy) |
 | `tools/post-execute` | `waterfall` | [`packages/core/tools/src/index.ts:105`](../packages/core/tools/src/index.ts) | [`tools`](../packages/core/tools) (`waterfall`) | [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex), [`repeat-tool-guard`](../packages/guard/repeat-tool-guard), [`spill-policy`](../packages/spill/spill-policy), [`workspace-context`](../packages/context/workspace-context) |
 | `tools/pre-execute` | `waterfall` | [`packages/core/tools/src/index.ts:82`](../packages/core/tools/src/index.ts) | [`tools`](../packages/core/tools) (`waterfall`) | [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex) |
 | `tools/result` | `emit` | [`packages/core/tools/src/index.ts:113`](../packages/core/tools/src/index.ts) | [`tools`](../packages/core/tools) (`events.dispatch`) | [`subagent-inprocess`](../packages/subagent/subagent-inprocess), [`workspace-context`](../packages/context/workspace-context) |
--- a/docs/module-graph.md
+++ b/docs/module-graph.md
@@ -98,6 +98,7 @@ flowchart TD
    pkg_hooks_codex["hooks-codex"]
  end
  subgraph group_session_persistence["packages/session-persistence"]
+    pkg_session_checkpoint_policy["session-checkpoint-policy"]
    pkg_session_persistence["session-persistence"]
    pkg_session_persistence_jsonl["session-persistence-jsonl"]
    pkg_session_persistence_sqlite["session-persistence-sqlite"]
@@ -148,6 +149,7 @@ flowchart TD
    pkg_code_runtime_worker["code-runtime-worker"]
  end
  subgraph group_context["packages/context"]
+    pkg_session_reference["session-reference"]
    pkg_time_context["time-context"]
    pkg_workspace_context["workspace-context"]
  end
@@ -174,6 +176,11 @@ flowchart TD
  subgraph group_mcp["packages/mcp"]
    pkg_mcp_client["mcp-client"]
  end
+  subgraph group_pty["packages/pty"]
+    pkg_pty["pty"]
+    pkg_pty_local["pty-local"]
+    pkg_tool_pty["tool-pty"]
+  end
  subgraph group_sandbox["packages/sandbox"]
    pkg_sandbox["sandbox"]
    pkg_sandbox_local["sandbox-local"]
@@ -203,7 +210,6 @@ flowchart TD
  pkg_subagent_subprocess --> pkg_invariants
  pkg_acp_snapshot --> pkg_invariants
  pkg_loader_smoke --> pkg_invariants
-  pkg_app_boot --> pkg_invariants
  pkg_client_connection --> pkg_invariants
  pkg_client_i18n --> pkg_invariants
  pkg_client_runtime --> pkg_invariants
@@ -227,8 +233,6 @@ flowchart TD
  pkg_code_runtime_worker --> pkg_invariants
  pkg_helper --> pkg_brand
  pkg_helper --> pkg_invariants
-  pkg_scripts --> pkg_app_boot
-  pkg_scripts --> pkg_invariants
  pkg_telemetry --> pkg_brand
  pkg_telemetry --> pkg_invariants
  pkg_telemetry --> pkg_paths
@@ -295,6 +299,9 @@ flowchart TD
  pkg_llm_replay --> pkg_invariants
  pkg_llm_replay --> pkg_llm
  pkg_llm_replay --> pkg_session
+  pkg_app_boot --> pkg_invariants
+  pkg_app_boot --> pkg_paths
+  pkg_app_boot --> pkg_system_prompt
  pkg_lsp_local --> pkg_brand
  pkg_lsp_local --> pkg_invariants
  pkg_lsp_local --> pkg_llm
@@ -372,6 +379,11 @@ flowchart TD
  pkg_time_context --> pkg_agent
  pkg_time_context --> pkg_invariants
  pkg_time_context --> pkg_session
+  pkg_pty --> pkg_agent
+  pkg_pty --> pkg_brand
+  pkg_pty --> pkg_invariants
+  pkg_scripts --> pkg_app_boot
+  pkg_scripts --> pkg_invariants
  pkg_tasks --> pkg_agent
  pkg_tasks --> pkg_brand
  pkg_tasks --> pkg_invariants
@@ -424,6 +436,17 @@ flowchart TD
  pkg_permission --> pkg_sandbox_policy
  pkg_permission --> pkg_session
  pkg_permission --> pkg_user_approval
+  pkg_session_reference --> pkg_agent
+  pkg_session_reference --> pkg_compact
+  pkg_session_reference --> pkg_invariants
+  pkg_session_reference --> pkg_llm
+  pkg_session_reference --> pkg_retention
+  pkg_session_reference --> pkg_session
+  pkg_session_reference --> pkg_session_query
+  pkg_pty_local --> pkg_invariants
+  pkg_pty_local --> pkg_pty
+  pkg_pty_local --> pkg_sandbox
+  pkg_pty_local --> pkg_sandbox_policy
  pkg_agent_loop --> pkg_agent
  pkg_agent_loop --> pkg_invariants
  pkg_agent_loop --> pkg_llm
@@ -516,6 +539,12 @@ flowchart TD
  pkg_hooks_codex --> pkg_session
  pkg_hooks_codex --> pkg_session_persistence
  pkg_hooks_codex --> pkg_tools
+  pkg_session_checkpoint_policy --> pkg_agent
+  pkg_session_checkpoint_policy --> pkg_invariants
+  pkg_session_checkpoint_policy --> pkg_llm
+  pkg_session_checkpoint_policy --> pkg_session
+  pkg_session_checkpoint_policy --> pkg_session_persistence
+  pkg_session_checkpoint_policy --> pkg_tools
  pkg_agent_loop_testkit --> pkg_agent
  pkg_agent_loop_testkit --> pkg_invariants
  pkg_agent_loop_testkit --> pkg_llm
@@ -545,6 +574,13 @@ flowchart TD
  pkg_mcp_client --> pkg_invariants
  pkg_mcp_client --> pkg_llm
  pkg_mcp_client --> pkg_tools
+  pkg_tool_pty --> pkg_agent
+  pkg_tool_pty --> pkg_invariants
+  pkg_tool_pty --> pkg_llm
+  pkg_tool_pty --> pkg_pty
+  pkg_tool_pty --> pkg_system_prompt
+  pkg_tool_pty --> pkg_tasks
+  pkg_tool_pty --> pkg_tools
  pkg_tool_tasks --> pkg_agent
  pkg_tool_tasks --> pkg_invariants
  pkg_tool_tasks --> pkg_system_prompt
@@ -594,6 +630,8 @@ 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
  pkg_acp --> pkg_tools
@@ -613,7 +651,10 @@ flowchart TD
  pkg_tui --> pkg_llm
  pkg_tui --> pkg_llm_retry
  pkg_tui --> pkg_session
+  pkg_tui --> pkg_session_persistence
+  pkg_tui --> pkg_session_reference
  pkg_tui --> pkg_session_title
+  pkg_tui --> pkg_skill
  pkg_tui --> pkg_system_prompt
  pkg_tui --> pkg_token_meter
  pkg_tui --> pkg_tools
@@ -668,7 +709,10 @@ flowchart TD
  pkg_acp_demo --> pkg_command_goal
  pkg_acp_demo --> pkg_commands
  pkg_acp_demo --> pkg_invariants
+  pkg_acp_demo --> pkg_session_checkpoint_policy
  pkg_acp_demo --> pkg_session_persistence_jsonl
+  pkg_acp_demo --> pkg_session_query
+  pkg_acp_demo --> pkg_session_reference
  pkg_acp_demo --> pkg_tools
  pkg_acp_demo --> pkg_user_interaction
  pkg_acp_demo --> pkg_workspace_context
@@ -678,6 +722,7 @@ flowchart TD
  pkg_cli_demo --> pkg_invariants
  pkg_cli_demo --> pkg_llm
  pkg_cli_demo --> pkg_session
+  pkg_cli_demo --> pkg_session_checkpoint_policy
  pkg_cli_demo --> pkg_session_persistence_jsonl
  pkg_cli_demo --> pkg_tools
  pkg_cli_demo --> pkg_workspace_context
@@ -690,7 +735,10 @@ flowchart TD
  pkg_tui_demo --> pkg_invariants
  pkg_tui_demo --> pkg_llm
  pkg_tui_demo --> pkg_session
+  pkg_tui_demo --> pkg_session_checkpoint_policy
  pkg_tui_demo --> pkg_session_persistence_jsonl
+  pkg_tui_demo --> pkg_session_query
+  pkg_tui_demo --> pkg_session_reference
  pkg_tui_demo --> pkg_tool_ask_user
  pkg_tui_demo --> pkg_tools
  pkg_tui_demo --> pkg_tui
@@ -710,7 +758,6 @@ flowchart TD
 | [`subagent-subprocess`](../packages/subagent/subagent-subprocess) | `subagent` | [`invariants`](../packages/support/invariants) |
 | [`acp-snapshot`](../packages/support/acp-snapshot) | `support` | [`invariants`](../packages/support/invariants) |
 | [`loader-smoke`](../packages/support/loader-smoke) | `support` | [`invariants`](../packages/support/invariants) |
-| [`app-boot`](../packages/ui/app-boot) | `ui` | [`invariants`](../packages/support/invariants) |
 | [`client-connection`](../packages/client/connection) | `client` | [`invariants`](../packages/support/invariants) |
 | [`client-i18n`](../packages/client/i18n) | `client` | [`invariants`](../packages/support/invariants) |
 | [`client-runtime`](../packages/client/runtime) | `client` | [`invariants`](../packages/support/invariants) |
@@ -731,7 +778,6 @@ flowchart TD
 | [`llm`](../packages/llm/llm) | `llm` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants) |
 | [`code-runtime-worker`](../packages/code-runtime/code-runtime-worker) | `code-runtime` | [`code-runtime`](../packages/code-runtime/code-runtime), [`invariants`](../packages/support/invariants) |
 | [`helper`](../packages/sdk/helper) | `sdk` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants) |
-| [`scripts`](../packages/sdk/scripts) | `sdk` | [`app-boot`](../packages/ui/app-boot), [`invariants`](../packages/support/invariants) |
 | [`telemetry`](../packages/sdk/telemetry) | `sdk` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`paths`](../packages/util/paths) |
 | [`llm-deepseek`](../packages/llm/llm-deepseek) | `llm` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`timeout`](../packages/util/timeout) |
 | [`llm-pi-ai`](../packages/llm/llm-pi-ai) | `llm` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`timeout`](../packages/util/timeout) |
@@ -754,6 +800,7 @@ flowchart TD
 | [`session-persistence`](../packages/session-persistence/session-persistence) | `session-persistence` | [`invariants`](../packages/support/invariants), [`session`](../packages/core/session) |
 | [`session-title`](../packages/session-title/session-title) | `session-title` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session) |
 | [`llm-replay`](../packages/support/llm-replay) | `support` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session) |
+| [`app-boot`](../packages/ui/app-boot) | `ui` | [`invariants`](../packages/support/invariants), [`paths`](../packages/util/paths), [`system-prompt`](../packages/core/system-prompt) |
 | [`lsp-local`](../packages/lsp/lsp-local) | `lsp` | [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`lsp`](../packages/lsp/lsp), [`timeout`](../packages/util/timeout) |
 | [`sandbox-local`](../packages/sandbox/sandbox-local) | `sandbox` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`sandbox`](../packages/sandbox/sandbox) |
 | [`sandbox-policy`](../packages/sandbox/sandbox-policy) | `sandbox` | [`invariants`](../packages/support/invariants), [`sandbox`](../packages/sandbox/sandbox), [`session`](../packages/core/session) |
@@ -774,6 +821,8 @@ flowchart TD
 | [`user-approval`](../packages/ui/user-approval) | `ui` | [`agent`](../packages/core/agent), [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`scope`](../packages/core/scope), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt) |
 | [`user-interaction`](../packages/ui/user-interaction) | `ui` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm) |
 | [`time-context`](../packages/context/time-context) | `context` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`session`](../packages/core/session) |
+| [`pty`](../packages/pty/pty) | `pty` | [`agent`](../packages/core/agent), [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants) |
+| [`scripts`](../packages/sdk/scripts) | `sdk` | [`app-boot`](../packages/ui/app-boot), [`invariants`](../packages/support/invariants) |
 | [`tasks`](../packages/tasks/tasks) | `tasks` | [`agent`](../packages/core/agent), [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`session`](../packages/core/session), [`timeout`](../packages/util/timeout) |
 | [`workflow`](../packages/workflow/workflow) | `workflow` | [`agent`](../packages/core/agent), [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session) |
 | [`tools`](../packages/core/tools) | `core` | [`agent`](../packages/core/agent), [`code-runtime`](../packages/code-runtime/code-runtime), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`scope`](../packages/core/scope), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt), [`user-approval`](../packages/ui/user-approval) |
@@ -784,6 +833,8 @@ flowchart TD
 | [`session-title-all-messages-llm`](../packages/session-title/session-title-all-messages-llm) | `session-title` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-title`](../packages/session-title/session-title), [`session-title-llm`](../packages/session-title/session-title-llm) |
 | [`session-title-first-message-llm`](../packages/session-title/session-title-first-message-llm) | `session-title` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-title`](../packages/session-title/session-title), [`session-title-llm`](../packages/session-title/session-title-llm) |
 | [`permission`](../packages/ui/permission) | `ui` | [`bash`](../packages/bash/bash), [`invariants`](../packages/support/invariants), [`sandbox`](../packages/sandbox/sandbox), [`sandbox-policy`](../packages/sandbox/sandbox-policy), [`session`](../packages/core/session), [`user-approval`](../packages/ui/user-approval) |
+| [`session-reference`](../packages/context/session-reference) | `context` | [`agent`](../packages/core/agent), [`compact`](../packages/compact/compact), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`retention`](../packages/util/retention), [`session`](../packages/core/session), [`session-query`](../packages/session-query/session-query) |
+| [`pty-local`](../packages/pty/pty-local) | `pty` | [`invariants`](../packages/support/invariants), [`pty`](../packages/pty/pty), [`sandbox`](../packages/sandbox/sandbox), [`sandbox-policy`](../packages/sandbox/sandbox-policy) |
 | [`agent-loop`](../packages/core/agent-loop) | `core` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`scope`](../packages/core/scope), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
 | [`tool-goal`](../packages/goal/tool-goal) | `goal` | [`agent`](../packages/core/agent), [`goal`](../packages/goal/goal), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
 | [`tool-bash`](../packages/bash/tool-bash) | `bash` | [`agent`](../packages/core/agent), [`bash`](../packages/bash/bash), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`paths`](../packages/util/paths), [`sandbox`](../packages/sandbox/sandbox), [`sandbox-policy`](../packages/sandbox/sandbox-policy), [`session-persistence`](../packages/session-persistence/session-persistence), [`system-prompt`](../packages/core/system-prompt), [`tasks`](../packages/tasks/tasks), [`tools`](../packages/core/tools), [`user-approval`](../packages/ui/user-approval) |
@@ -798,26 +849,28 @@ flowchart TD
 | [`plan-mode`](../packages/plan/plan-mode) | `plan` | [`agent`](../packages/core/agent), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction) |
 | [`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) |
+| [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy) | `session-persistence` | [`agent`](../packages/core/agent), [`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) |
 | [`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) |
 | [`tool-lsp`](../packages/lsp/tool-lsp) | `lsp` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`lsp`](../packages/lsp/lsp), [`system-prompt`](../packages/core/system-prompt), [`timeout`](../packages/util/timeout), [`tools`](../packages/core/tools) |
 | [`mcp-client`](../packages/mcp/mcp-client) | `mcp` | [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`tools`](../packages/core/tools) |
+| [`tool-pty`](../packages/pty/tool-pty) | `pty` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`pty`](../packages/pty/pty), [`system-prompt`](../packages/core/system-prompt), [`tasks`](../packages/tasks/tasks), [`tools`](../packages/core/tools) |
 | [`tool-tasks`](../packages/tasks/tool-tasks) | `tasks` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`system-prompt`](../packages/core/system-prompt), [`tasks`](../packages/tasks/tasks), [`tools`](../packages/core/tools) |
 | [`tool-workflow`](../packages/workflow/tool-workflow) | `workflow` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools), [`workflow`](../packages/workflow/workflow) |
 | [`subagent-acp`](../packages/subagent/subagent-acp) | `subagent` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`subagent`](../packages/subagent/subagent), [`subagent-subprocess`](../packages/subagent/subagent-subprocess) |
 | [`subagent-inprocess`](../packages/subagent/subagent-inprocess) | `subagent` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`subagent`](../packages/subagent/subagent), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
 | [`tool-subagent`](../packages/subagent/tool-subagent) | `subagent` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`subagent`](../packages/subagent/subagent), [`tasks`](../packages/tasks/tasks), [`tools`](../packages/core/tools) |
 | [`hooks-claude`](../packages/hooks/hooks-claude) | `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), [`subagent`](../packages/subagent/subagent), [`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), [`plan-mode`](../packages/plan/plan-mode), [`sandbox`](../packages/sandbox/sandbox), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`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), [`plan-mode`](../packages/plan/plan-mode), [`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) |
 | [`jsonrpc`](../packages/ui/jsonrpc) | `ui` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`llm-deepseek`](../packages/llm/llm-deepseek), [`scope`](../packages/core/scope), [`session`](../packages/core/session), [`subagent`](../packages/subagent/subagent) |
-| [`tui`](../packages/ui/tui) | `ui` | [`agent`](../packages/core/agent), [`agent-loop`](../packages/core/agent-loop), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`llm-retry`](../packages/llm/llm-retry), [`session`](../packages/core/session), [`session-title`](../packages/session-title/session-title), [`system-prompt`](../packages/core/system-prompt), [`token-meter`](../packages/llm/token-meter), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction) |
+| [`tui`](../packages/ui/tui) | `ui` | [`agent`](../packages/core/agent), [`agent-loop`](../packages/core/agent-loop), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`llm-retry`](../packages/llm/llm-retry), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`session-reference`](../packages/context/session-reference), [`session-title`](../packages/session-title/session-title), [`skill`](../packages/skill/skill), [`system-prompt`](../packages/core/system-prompt), [`token-meter`](../packages/llm/token-meter), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction) |
 | [`agent-spine-demo`](../packages/examples/agent-spine-demo) | `examples` | [`agent`](../packages/core/agent), [`agent-loop`](../packages/core/agent-loop), [`goal`](../packages/goal/goal), [`goal-session`](../packages/goal/goal-session), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`llm-retry`](../packages/llm/llm-retry), [`paths`](../packages/util/paths), [`scope`](../packages/core/scope), [`session`](../packages/core/session), [`session-title`](../packages/session-title/session-title), [`skill`](../packages/skill/skill), [`skill-local`](../packages/skill/skill-local), [`system-prompt`](../packages/core/system-prompt), [`tasks`](../packages/tasks/tasks), [`tool-bash`](../packages/bash/tool-bash), [`tool-goal`](../packages/goal/tool-goal), [`tool-skill`](../packages/skill/tool-skill), [`tool-tasks`](../packages/tasks/tool-tasks), [`tools`](../packages/core/tools), [`workspace-context`](../packages/context/workspace-context) |
 | [`tool-ralph`](../packages/workflow/tool-ralph) | `workflow` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`subagent`](../packages/subagent/subagent), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools), [`workflow`](../packages/workflow/workflow) |
 | [`workflow-workerthread`](../packages/workflow/workflow-workerthread) | `workflow` | [`agent`](../packages/core/agent), [`brand`](../packages/util/brand), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`subagent`](../packages/subagent/subagent), [`tools`](../packages/core/tools), [`workflow`](../packages/workflow/workflow) |
 | [`subagent-fork`](../packages/subagent/subagent-fork) | `subagent` | [`agent`](../packages/core/agent), [`invariants`](../packages/support/invariants), [`session`](../packages/core/session), [`subagent`](../packages/subagent/subagent), [`subagent-inprocess`](../packages/subagent/subagent-inprocess) |
 | [`subagent-spawn`](../packages/subagent/subagent-spawn) | `subagent` | [`invariants`](../packages/support/invariants), [`subagent`](../packages/subagent/subagent), [`subagent-inprocess`](../packages/subagent/subagent-inprocess) |
-| [`acp-demo`](../packages/examples/acp-demo) | `examples` | [`acp`](../packages/ui/acp), [`agent-spine-demo`](../packages/examples/agent-spine-demo), [`app-boot`](../packages/ui/app-boot), [`command-goal`](../packages/goal/command-goal), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction), [`workspace-context`](../packages/context/workspace-context) |
-| [`cli-demo`](../packages/examples/cli-demo) | `examples` | [`agent`](../packages/core/agent), [`agent-spine-demo`](../packages/examples/agent-spine-demo), [`app-boot`](../packages/ui/app-boot), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`tools`](../packages/core/tools), [`workspace-context`](../packages/context/workspace-context) |
-| [`tui-demo`](../packages/examples/tui-demo) | `examples` | [`agent`](../packages/core/agent), [`agent-loop`](../packages/core/agent-loop), [`agent-spine-demo`](../packages/examples/agent-spine-demo), [`app-boot`](../packages/ui/app-boot), [`command-goal`](../packages/goal/command-goal), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`tool-ask-user`](../packages/ui/tool-ask-user), [`tools`](../packages/core/tools), [`tui`](../packages/ui/tui), [`user-interaction`](../packages/ui/user-interaction), [`workspace-context`](../packages/context/workspace-context) |
+| [`acp-demo`](../packages/examples/acp-demo) | `examples` | [`acp`](../packages/ui/acp), [`agent-spine-demo`](../packages/examples/agent-spine-demo), [`app-boot`](../packages/ui/app-boot), [`command-goal`](../packages/goal/command-goal), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`session-query`](../packages/session-query/session-query), [`session-reference`](../packages/context/session-reference), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction), [`workspace-context`](../packages/context/workspace-context) |
+| [`cli-demo`](../packages/examples/cli-demo) | `examples` | [`agent`](../packages/core/agent), [`agent-spine-demo`](../packages/examples/agent-spine-demo), [`app-boot`](../packages/ui/app-boot), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`tools`](../packages/core/tools), [`workspace-context`](../packages/context/workspace-context) |
+| [`tui-demo`](../packages/examples/tui-demo) | `examples` | [`agent`](../packages/core/agent), [`agent-loop`](../packages/core/agent-loop), [`agent-spine-demo`](../packages/examples/agent-spine-demo), [`app-boot`](../packages/ui/app-boot), [`command-goal`](../packages/goal/command-goal), [`commands`](../packages/ui/commands), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`session-query`](../packages/session-query/session-query), [`session-reference`](../packages/context/session-reference), [`tool-ask-user`](../packages/ui/tool-ask-user), [`tools`](../packages/core/tools), [`tui`](../packages/ui/tui), [`user-interaction`](../packages/ui/user-interaction), [`workspace-context`](../packages/context/workspace-context) |
--- 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:67`](../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/*`

@@ -357,7 +357,7 @@ Source: [`packages/plan/plan-mode/src/index.ts:40`](../packages/plan/plan-mode/s

 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/*`

@@ -371,7 +371,7 @@ 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/*`

@@ -405,7 +405,7 @@ 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

@@ -424,12 +424,10 @@ 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/*`

@@ -440,7 +438,7 @@ 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

@@ -449,7 +447,7 @@ 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/*`

@@ -462,7 +460,7 @@ 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/*`

@@ -479,7 +477,7 @@ 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

@@ -523,7 +521,7 @@ 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/*`

@@ -541,7 +539,7 @@ 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

@@ -557,7 +555,7 @@ 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/*`

@@ -565,9 +563,7 @@ 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)
--- a/docs/tool-catalog.md
+++ b/docs/tool-catalog.md
@@ -22,12 +22,13 @@ This table connects model-visible tool names to the plugin package and service s
 | `@deepseek-ai/dsh-tool-cordis` | `cordis_inspect`, `cordis_mount`, `cordis_unmount` | `ctx.tools` | `tool/call`, `tool/result`, `live plugin-tree mutations (mount/unmount)` | - | Ships in examples/cordis-agent only (a deliberate opt-in — mounted code gets the real ctx, see .agents/notes/implemented/feature/2026-07-08-self-referential-cordis-toolset.md). Plugins the model mounts may register ADDITIONAL model-visible tools at runtime; a full changed request header logs those tool-set changes. |
 | `@deepseek-ai/dsh-tool-fs` | `edit`, `read`, `write` | `ctx.tools`, `ctx.fs`, `ctx.systemPrompt` | `tool/call`, `fs/write-intent or fs/edit-intent for mutations`, `fs/observed after successful file operations`, `tool/result` | - | The read-before-write/edit policy is added by `@deepseek-ai/dsh-fs-policy` (an `fs/*` event-gate plugin, no schema change); a deployment that loads these tools is expected to also load it. The tool schemas above are identical with or without the policy plugin. |
 | `@deepseek-ai/dsh-tool-fs-search` | `glob`, `grep` | `ctx.tools`, `ctx.bash`, `ctx.systemPrompt` | `tool/call`, `tool/result` | - | glob and grep are conditional bash-backed discovery tools: they register only when ctx.bash can find `rg`, then run fixed ripgrep commands through ctx.bash as ordinary foreground calls (never background tasks). Capped results save the complete formatted list through the optional ctx.spillStore backend; returned locators are follow-up-readable/searchable when the backend exposes local paths in co-located deployments. |
+| `@deepseek-ai/dsh-tool-pty` | `terminal_close`, `terminal_list`, `terminal_open`, `terminal_read`, `terminal_send`, `terminal_signal` | `ctx.tools`, `ctx.pty`, `ctx.systemPrompt`, `ctx.tasks at call time for run_in_background` | `tool/call`, `tool/result` | - | The six terminal tools are opt-in and complement one-shot bash/filesystem tools. `terminal_send(run_in_background: true)` registers with `ctx.tasks`; TUI, named key sequences, BEL, resize, auto-start, and cross-agent sharing are absent from the schema. |
 | `@deepseek-ai/dsh-tool-goal` | `create_goal`, `get_goal`, `update_goal` | `ctx.tools`, `ctx.agents`, `ctx.goals`, `ctx.systemPrompt`, `a calling Agent in an authorized open turn` | `tool/call`, `context/message goal snapshot for mutations`, `tool/result` | - | create, edit, pause, and resume require direct-human root authority; complete and blocked also accept the exact current goal round. The default blocked lower bound is three admitted rounds. |
 | `@deepseek-ai/dsh-tool-lsp` | `lsp` | `ctx.tools`, `ctx.lsp`, `ctx.systemPrompt` | `tool/call`, `tool/result` | - | The lsp tool keeps provider selection and language-server subprocesses behind ctx.lsp, so its model-visible schema stays stable across providers. Requires a registered provider (e.g. `@deepseek-ai/dsh-lsp-local`) at runtime; without one, a query returns the structured `LSP_UNAVAILABLE` error rather than changing the schema. |
 | `@deepseek-ai/dsh-tool-ralph` | `ralph` | `ctx.tools`, `ctx.workflows`, `ctx.subagents`, `ctx.systemPrompt`, `a calling Agent (exec.agent parents every fresh round)` | `tool/call`, `tool/result`, `workflow and child session events during execution` | - | A fixed foreground workflow starts one fresh structured child per round; the model selects only the immutable objective and an optional round cap. |
 | `@deepseek-ai/dsh-tool-skill` | `skill` | `ctx.tools`, `ctx.skills` | `tool/call`, `tool/result` | - | - |
 | `@deepseek-ai/dsh-tool-subagent` | `subagent` | `ctx.tools`, `ctx.subagents` | `tool/call`, `tool/result`, `child session events through the chosen provider` | `subagent`, `subagent_fork` | The registered tool name is the load-time `toolName` config (default `subagent`); the schema above is that default. The shipped example agents load this package once per subagent backend, so the model additionally sees `subagent_fork` (bound to the fork backend) with an identical schema — see `examples/tui-agent/cordis.yml` and `examples/acp-agent/cordis.yml`. |
-| `@deepseek-ai/dsh-tool-tasks` | `task_kill`, `task_list`, `task_output` | `ctx.tools`, `ctx.tasks`, `ctx.systemPrompt` | `tool/call`, `tool/result`, `context/message via agent.inject() for background completion notices` | - | The kind-agnostic background-task control surface: a background bash command and a background subagent are read, listed, and killed through the same three tools. Loading the plugin attaches the control surface that arms producers' `ctx.tasks.start()`. |
+| `@deepseek-ai/dsh-tool-tasks` | `task_kill`, `task_list`, `task_output` | `ctx.tools`, `ctx.tasks`, `ctx.systemPrompt` | `tool/call`, `tool/result`, `context/message via agent.inject() for background completion notices` | - | The kind-agnostic background-task control surface: background bash commands, PTY sends, and subagents are read, listed, and killed through the same three tools. Loading the plugin attaches the control surface that arms producers' `ctx.tasks.start()`. |
 | `@deepseek-ai/dsh-tool-todo` | `todo_write` | `ctx.tools`, `owning Agent session` | `tool/call`, `todo/write`, `tool/result` | - | todo_write is session-owned state; UIs render the latest todo/write event as a checklist or ACP plan. |
 | `@deepseek-ai/dsh-tool-workflow` | `workflow` | `ctx.tools`, `ctx.workflows`, `ctx.systemPrompt`, `a calling Agent (exec.agent parents the script children)` | `tool/call`, `tool/result` | - | - |
 | `@deepseek-ai/dsh-tool-web` | `web_fetch`, `web_search` | `ctx.tools`, `ctx.web`, `ctx.systemPrompt` | `tool/call`, `tool/result` | - | web_search and web_fetch keep provider selection behind ctx.web so model-visible schemas stay stable across backend swaps. |
@@ -422,6 +423,169 @@ Source: [`packages/fs/tool-fs-search/src/index.ts`](../packages/fs/tool-fs-searc

 glob and grep are conditional bash-backed discovery tools: they register only when ctx.bash can find `rg`, then run fixed ripgrep commands through ctx.bash as ordinary foreground calls (never background tasks). Capped results save the complete formatted list through the optional ctx.spillStore backend; returned locators are follow-up-readable/searchable when the backend exposes local paths in co-located deployments.

+## `@deepseek-ai/dsh-tool-pty`
+
+### `terminal_close`
+
+Close one persistent terminal and wait until its captured owned process tree is gone.
+
+```json
+{
+  "type": "object",
+  "properties": {
+    "sessionId": {
+      "type": "string",
+      "description": "Terminal session id."
+    }
+  },
+  "required": [
+    "sessionId"
+  ]
+}
+```
+
+Source: [`packages/pty/tool-pty/src/index.ts`](../packages/pty/tool-pty/src/index.ts)
+
+### `terminal_list`
+
+List persistent terminal sessions owned by the current agent.
+
+```json
+{
+  "type": "object",
+  "properties": {}
+}
+```
+
+Source: [`packages/pty/tool-pty/src/index.ts`](../packages/pty/tool-pty/src/index.ts)
+
+### `terminal_open`
+
+Create a persistent, owner-isolated terminal session from a registered backend type. Use this for shell or REPL state that must survive across tool calls.
+
+```json
+{
+  "type": "object",
+  "properties": {
+    "type": {
+      "type": "string",
+      "description": "Registered terminal backend type, usually \"shell\"."
+    },
+    "name": {
+      "type": "string",
+      "description": "Optional owner-local display name such as \"main\" or \"gdb\"."
+    },
+    "cwd": {
+      "type": "string",
+      "description": "Initial working directory. Defaults to the deployment workspace root."
+    }
+  },
+  "required": [
+    "type"
+  ]
+}
+```
+
+Source: [`packages/pty/tool-pty/src/index.ts`](../packages/pty/tool-pty/src/index.ts)
+
+### `terminal_read`
+
+Read a bounded page of retained output from a persistent terminal without sending input.
+
+```json
+{
+  "type": "object",
+  "properties": {
+    "sessionId": {
+      "type": "string",
+      "description": "Terminal session id."
+    },
+    "offset": {
+      "type": "number",
+      "description": "Newest-relative line offset (default 0)."
+    },
+    "count": {
+      "type": "number",
+      "description": "Requested line count (default 500; backend caps apply)."
+    }
+  },
+  "required": [
+    "sessionId"
+  ]
+}
+```
+
+Source: [`packages/pty/tool-pty/src/index.ts`](../packages/pty/tool-pty/src/index.ts)
+
+### `terminal_send`
+
+Send text to a persistent terminal. By default Enter is submitted and the call waits for a prompt, stdin wait, output silence, timeout, or session exit. Background mode returns a task id for task_output/task_kill.
+
+```json
+{
+  "type": "object",
+  "properties": {
+    "sessionId": {
+      "type": "string",
+      "description": "Terminal session id returned by terminal_open or terminal_list."
+    },
+    "text": {
+      "type": "string",
+      "description": "UTF-8 text to write to the terminal."
+    },
+    "submit": {
+      "type": "boolean",
+      "description": "Submit Enter after text (default true). Set false for control characters or incomplete REPL input."
+    },
+    "run_in_background": {
+      "type": "boolean",
+      "description": "Return a task id immediately; collect with task_output or stop with task_kill."
+    }
+  },
+  "required": [
+    "sessionId",
+    "text"
+  ]
+}
+```
+
+Source: [`packages/pty/tool-pty/src/index.ts`](../packages/pty/tool-pty/src/index.ts)
+
+### `terminal_signal`
+
+Send an allowed signal to the current foreground process group of a persistent terminal.
+
+```json
+{
+  "type": "object",
+  "properties": {
+    "sessionId": {
+      "type": "string",
+      "description": "Terminal session id."
+    },
+    "signal": {
+      "type": "string",
+      "description": "Signal to deliver. Shell-targeted SIGKILL is rejected; use terminal_close.",
+      "enum": [
+        "SIGINT",
+        "SIGTERM",
+        "SIGKILL",
+        "SIGTSTP",
+        "SIGHUP"
+      ]
+    }
+  },
+  "required": [
+    "sessionId",
+    "signal"
+  ]
+}
+```
+
+Source: [`packages/pty/tool-pty/src/index.ts`](../packages/pty/tool-pty/src/index.ts)
+
+The six terminal tools are opt-in and complement one-shot bash/filesystem tools. `terminal_send(run_in_background: true)` registers with `ctx.tasks`; TUI, named key sequences, BEL, resize, auto-start, and cross-agent sharing are absent from the schema.
+
 ## `@deepseek-ai/dsh-tool-goal`

 ### `create_goal`
@@ -715,7 +879,7 @@ Read a background task. Stream tasks return only output since the previous read;

 Source: [`packages/tasks/tool-tasks/src/index.ts`](../packages/tasks/tool-tasks/src/index.ts)

-The kind-agnostic background-task control surface: a background bash command and a background subagent are read, listed, and killed through the same three tools. Loading the plugin attaches the control surface that arms producers' `ctx.tasks.start()`.
+The kind-agnostic background-task control surface: background bash commands, PTY sends, and subagents are read, listed, and killed through the same three tools. Loading the plugin attaches the control surface that arms producers' `ctx.tasks.start()`.

 ## `@deepseek-ai/dsh-tool-todo`