Merge remote-tracking branch 'origin/master' into codex/tool-json-schema-dsl

# Conflicts: # scripts/type-equiv.manifest.json
2026-07-22 23:34:17 +08:00
parent a03ed8d60b 690c53dc03
commit 065d20c249
159 changed files with 3917 additions and 361 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: 905cb4a202f7278bbb2694b90b498c85fee3217b
-architecture.zh.md: 451ae1a048c1c5f7d5100192980bdfc0d5275798
+architecture.md: 6ff2aa1ad4ca2ef051322f9d95631fe626d26e84
+architecture.zh.md: b4b26efec16d85f1fb26589c5c9bffbb35e39564
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -81,11 +81,11 @@ 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
@@ -123,7 +123,7 @@ 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)).

--- a/docs/architecture.zh.md
+++ b/docs/architecture.zh.md
@@ -81,11 +81,11 @@ 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
@@ -123,7 +123,7 @@ 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)）。

--- 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"]
@@ -54,7 +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"]
@@ -153,6 +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
@@ -214,6 +217,9 @@ flowchart LR
  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
@@ -263,7 +269,8 @@ 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-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. |
--- 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`

@@ -64,6 +64,8 @@ export interface Config {
  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. */
@@ -79,9 +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:41`](../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`

@@ -1009,6 +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`
@@ -1025,7 +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`

@@ -1570,7 +1590,7 @@ export interface TuiConfig {
 }
 ```

-Source: [`packages/ui/tui/src/index.ts:145`](../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`

@@ -1597,6 +1617,8 @@ export interface Config {
  persistenceRoot?: string
  /** JSONL artifact encoding; defaults to checksummed Zstandard frames. */
  persistenceCompression?: JsonlCompression
+  /** Cross-session reference discovery and snapshot byte budgets. */
+  sessionReferences?: SessionReferenceConfig
  /** TUI transcript's optional first line; absent renders nothing on start. */
  welcome?: string
  /**
@@ -1623,9 +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`

--- 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:70`](../../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:80`](../../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:92`](../../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:102`](../../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)

@@ -959,6 +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.
@@ -983,9 +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`

@@ -1134,7 +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:594`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:605`](../../packages/core/session/src/index.ts)

 ## `ctx.sessionTitle` — `SessionTitleService`

@@ -1168,7 +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/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
@@ -359,11 +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
 }
@@ -391,7 +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

@@ -443,15 +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
 }
@@ -461,10 +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/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.

--- a/docs/event-producer-consumer.md
+++ b/docs/event-producer-consumer.md
@@ -8,22 +8,22 @@ This matrix shows which packages dispatch each harness-owned event and which pac
 | Event | Mode | Declared in | Dispatchers | Listeners |
 | --- | --- | --- | --- | --- |
 | `agent-loop/config-start-failed` | `emit` | [`packages/core/agent-loop/src/index.ts:353`](../packages/core/agent-loop/src/index.ts) | [`agent-loop`](../packages/core/agent-loop) (`events.dispatch`) | [`tui`](../packages/ui/tui) |
-| `agent/cancel-requested` | `emit` | [`packages/core/agent/src/types.ts: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), [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy) |
-| `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), [`tui`](../packages/ui/tui) |
-| `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) |
@@ -31,10 +31,10 @@ This matrix shows which packages dispatch each harness-owned event and which pac
 | `fs/write-intent` | `waterfall` | [`packages/fs/fs/src/index.ts:54`](../packages/fs/fs/src/index.ts) | [`tool-fs`](../packages/fs/tool-fs) (`waterfall`) | [`fs-policy`](../packages/fs/fs-policy) |
 | `goal/changed` | `emit` | [`packages/goal/goal/src/types.ts:167`](../packages/goal/goal/src/types.ts) | [`goal`](../packages/goal/goal) (`emit`) | [`goal-session`](../packages/goal/goal-session) |
 | `llm/stream` | `waterfall` | [`packages/llm/llm/src/index.ts:52`](../packages/llm/llm/src/index.ts) | [`llm`](../packages/llm/llm) (`waterfall`) | [`agent-loop`](../packages/core/agent-loop), [`llm`](../packages/llm/llm), [`llm-replay`](../packages/support/llm-replay), [`session-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy), [`session-title`](../packages/session-title/session-title) |
-| `session/created` | `emit` | [`packages/core/session/src/index.ts:70`](../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:80`](../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:92`](../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:102`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`session-persistence`](../packages/session-persistence/session-persistence) |
+| `session/created` | `emit` | [`packages/core/session/src/index.ts: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) |
--- a/docs/module-graph.md
+++ b/docs/module-graph.md
@@ -149,6 +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
@@ -435,6 +436,13 @@ 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
@@ -622,6 +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
@@ -642,6 +652,7 @@ flowchart TD
  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
@@ -700,6 +711,8 @@ flowchart TD
  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
@@ -724,6 +737,8 @@ flowchart TD
  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
@@ -818,6 +833,7 @@ 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) |
@@ -847,14 +863,14 @@ flowchart TD
 | [`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-persistence`](../packages/session-persistence/session-persistence), [`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) |
+| [`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-checkpoint-policy`](../packages/session-persistence/session-checkpoint-policy), [`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) |
+| [`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), [`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) |
+| [`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)