diff --git a/.agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.i18n.yaml b/.agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.i18n.yaml
similarity index 100%
rename from .agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.i18n.yaml
rename to .agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.i18n.yaml
diff --git a/.agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.md b/.agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.md
similarity index 94%
rename from .agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.md
rename to .agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.md
index ada6d222f2..27da3f1c27 100644
--- a/.agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.md
+++ b/.agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.md
@@ -1,6 +1,6 @@
 # Agent Note: Separate context injection from turn execution
 
-Status: proposed
+Status: implemented
 
 English | [中文](2026-07-24-separate-context-injection-from-turn-execution.zh.md)
 
@@ -14,7 +14,7 @@ Idle `inject()` exposes a second mismatch. Injection does not request model exec
 
 `HookContext` also names its producer rather than its role. The value may come from a native plugin, a hook bridge, prompt admission, or tool post-processing. Its stable meaning is simply additional model-facing context with provenance.
 
-## Proposal
+## Decision
 
 Make `inject()` the only caller-facing operation for adding supplementary model-facing input, and define a turn exclusively as one execution of the model loop.
 
@@ -42,7 +42,7 @@ Caller-driven injection and hook-produced additional context deliberately have d
 
 Cross-session references follow the ordinary composition: the host prepares the snapshot, injects it with session-reference provenance, then sends or steers the readable direct prompt. The target log contains two simple messages, so later source mutation cannot change replay and transcript consumers do not need a prompt envelope. This supersedes the attachment mechanism in the [cross-session reference decision](../../implemented/feature/2026-07-21-cross-session-references.md) while retaining its snapshot and trust-boundary rules.
 
-This proposal preserves the caller-owned framing decision from [unwrapped injected content](../../implemented/simplification/2026-07-20-unwrap-injected-content-envelopes.md), the one-item turn rule from [one send, one turn](../../implemented/simplification/2026-07-17-one-send-one-turn.md), and narrows the [turn-enclosure decision](../../implemented/architecture/2026-06-15-turn-enclosure-invariant.md) so turns enclose execution rather than every session event.
+This decision preserves the caller-owned framing decision from [unwrapped injected content](../simplification/2026-07-20-unwrap-injected-content-envelopes.md), the one-item turn rule from [one send, one turn](../simplification/2026-07-17-one-send-one-turn.md), and narrows the [turn-enclosure decision](2026-06-15-turn-enclosure-invariant.md) so turns enclose execution rather than every session event.
 
 ## Alternatives considered
 
@@ -56,7 +56,7 @@ This proposal preserves the caller-owned framing decision from [unwrapped inject
 
 **Let hooks call `inject()` directly instead of returning additional contexts.** Direct injection would erase the extension point's admission ownership: a listener could append context before a downstream listener blocks the operation. Returning `additionalContexts` keeps the waterfall result authoritative while sharing the same post-admission outbox path.
 
-## Acceptance criteria
+## Verification
 
 - `SendOptions` and steering inbox records contain no attached contexts; `agent/queued` reports only the retained message and steering facts.
 - `UserMessageData` replaces `HookContext` across prompt interception, tool execution, hook bridges, guards, and context producers.
@@ -66,7 +66,7 @@ This proposal preserves the caller-owned framing decision from [unwrapped inject
 - Blocked prompt admission opens no turn and appends neither the prompt nor hook-produced additional contexts; independently injected caller context remains.
 - Unit, persistence/resume, invariant, ACP/TUI replay, and keyless assembled-application snapshots cover the new event order and durability semantics.
 
-## Risks
+## Consequences
 
 - Allowing one surface event outside turns weakens a simple invariant and may expose hidden assumptions in persistence scanning, crash repair, forking, compaction, and session queries.
 - Consecutive user-role messages replace one baked prompt message; provider adapters and cache behavior must accept and preserve that ordering.
diff --git a/.agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.zh.md b/.agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.zh.md
similarity index 99%
rename from .agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.zh.md
rename to .agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.zh.md
index 85cad4bef7..7c3946043b 100644
--- a/.agents/notes/proposed/architecture/2026-07-24-separate-context-injection-from-turn-execution.zh.md
+++ b/.agents/notes/implemented/architecture/2026-07-24-separate-context-injection-from-turn-execution.zh.md
@@ -1,6 +1,6 @@
 # Agent Note: 将上下文注入与轮次执行分离
 
-Status: proposed
+Status: implemented
 
 [English](2026-07-24-separate-context-injection-from-turn-execution.md) | 中文
 
diff --git a/packages/client/runtime/src/client/sessions/session.ts b/packages/client/runtime/src/client/sessions/session.ts
index d0333d97d6..1dd0283429 100644
--- a/packages/client/runtime/src/client/sessions/session.ts
+++ b/packages/client/runtime/src/client/sessions/session.ts
@@ -108,11 +108,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
   private dispatchesRev = 0
   private dispatchesCache: { rev: number; value: ReadonlyMap<string, readonly CodeSubCall[]> } | null = null
   private running = false
-  /** Whether a turn is open on the live stream — set on turn/start, cleared on
-   *  turn/end. A session/queued frame arriving while this is true joined the
-   *  steering FIFO; the host no longer stamps steering on the frame, so the
-   *  client derives it from the same ordered turn boundaries the host saw. */
-  private turnOpen = false
   /**
    * Sticky send marker, private input of the composerPhase derivation: set
    * synchronously before prompt()'s first await, never reset — the blank →
@@ -342,12 +337,6 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
     switch (frame.type) {
       case 'session/event': {
         this.retireQueued(frame.event)
-        // Track turn-open state AFTER retirement (a message turn/start first
-        // claims its queued entry, then opens the turn), so a later queued
-        // frame is stamped steering iff a turn is open — the host no longer
-        // stamps it on the frame.
-        if (frame.event.type === 'turn/start') this.turnOpen = true
-        else if (frame.event.type === 'turn/end') this.turnOpen = false
         this.acceptLiveEvent(frame.event, frame.view)
         return
       }
@@ -357,7 +346,7 @@ export class Session implements ObservableSnapshot<ConversationSnapshot> {
         const key = 'rpcId' in frame.source ? String(frame.source.rpcId) : `f:${rpcId}`
         this.queued.push({
           row: { key, preview: queuePreviewOf(frame.content) },
-          steering: this.turnOpen,
+          steering: frame.steering,
           sourceJson: JSON.stringify(frame.source),
         })
         this.queueRev++
diff --git a/packages/client/runtime/tests/queue-store.spec.ts b/packages/client/runtime/tests/queue-store.spec.ts
index 8481243cb7..6fe9f33c80 100644
--- a/packages/client/runtime/tests/queue-store.spec.ts
+++ b/packages/client/runtime/tests/queue-store.spec.ts
@@ -17,10 +17,11 @@ const text = (t: string): ContentBlock[] => [{ type: 'text', text: t }]
 const rid = (id: string): RpcId => id as RpcId
 
 /** session/queued frame with the wire-sourced rpcId key (the host prompt path). */
-function queuedFrame(body: string, rpcId: string): MuxFrame {
+function queuedFrame(body: string, rpcId: string, steering = false): MuxFrame {
   return {
     type: 'session/queued', sessionId: SID, content: text(body),
     source: { kind: 'user', rpcId: rid(rpcId) } as never,
+    steering,
   }
 }
 
@@ -42,6 +43,7 @@ describe('queue intake', () => {
       type: 'session/queued', sessionId: SID,
       content: [{ type: 'text', text: 'hi' }, { type: 'image', data: 'x' } as never],
       source: { kind: 'plugin', plugin: 'loop' },
+      steering: false,
     })
     expect(session.getSnapshot().queue).toEqual([{ key: 'f:env-2', preview: 'hi [image]' }])
   })
@@ -86,14 +88,7 @@ describe('queue retirement (host queuedMirror rules)', () => {
   it('steering/message drains the source-matched steering row only', () => {
     const session = makeSession()
     session.handleMuxEnvelope(rid('e1'), queuedFrame('普通', 'p-1')) // idle → non-steering
-    // Injection-triggered turn/start opens the turn without claiming a row, so
-    // the next queued frame is derived steering (arrived mid-turn).
-    const injection = {
-      ...ev.turnStart(0, 0),
-      data: { turn: 0, trigger: { kind: 'injection', source: { kind: 'plugin', plugin: 'x' } } },
-    } as never
-    session.handleMuxEnvelope(rid('e2'), { type: 'session/event', sessionId: SID, event: injection })
-    session.handleMuxEnvelope(rid('e3'), queuedFrame('插话', 'p-2')) // turn open → steering
+    session.handleMuxEnvelope(rid('e3'), queuedFrame('插话', 'p-2', true))
     // Loop-authored steering (different source) must not consume the user entry.
     const foreignSteering = {
       seq: 0, time: 1,
@@ -151,6 +146,19 @@ describe('queue reconnect semantics', () => {
     await session.resync()
     expect(session.getSnapshot().queue.map(r => r.key)).toEqual(['p-fresh'])
   })
+
+  it('replayed steering retires without a replayed turn/start', () => {
+    const session = makeSession()
+    session.handleMuxEnvelope(rid('e1'), { type: 'session/subscribed', sessionId: SID, lastSeq: 5 })
+    session.handleMuxEnvelope(rid('e2'), queuedFrame('重连插话', 'p-steer', true))
+    const committed = {
+      seq: 6, time: 2,
+      type: 'steering/message', surfaceOp: 'append',
+      data: { turn: 1, content: text('重连插话'), source: { kind: 'user', rpcId: rid('p-steer') } },
+    } as never
+    session.handleMuxEnvelope(rid('e3'), { type: 'session/event', sessionId: SID, event: committed })
+    expect(session.getSnapshot().queue).toEqual([])
+  })
 })
 
 describe('manager buffering of queued frames', () => {
diff --git a/packages/core/agent-loop/src/agent.ts b/packages/core/agent-loop/src/agent.ts
index ba5ec3dae9..6a3c68e959 100644
--- a/packages/core/agent-loop/src/agent.ts
+++ b/packages/core/agent-loop/src/agent.ts
@@ -17,6 +17,7 @@ import type {
   Agent,
   CancelOptions,
   AgentInterruptReason,
+  InboxPlacement,
   AgentOptions,
   AgentStatus,
   SettleReason,
@@ -51,6 +52,8 @@ export class ReactLoopAgent implements Agent {
 
   /** Whether observers see a running interval; consecutive turns share it. */
   private busy = false
+  /** Whether next-step input belongs to the current admission or open turn. */
+  private acceptingNextStep = false
   /** Abort owner for the current admission or turn. */
   private abort: AbortController | undefined
   /** Coalesced retry capability scoped to the active request-error waterfall. */
@@ -96,7 +99,7 @@ export class ReactLoopAgent implements Agent {
     const { target, wakeup } = options
     const id = AgentMessageId(randomUUID())
     if (target === 'next-step' && !wakeup) {
-      if (this.turnOpen) {
+      if (this.acceptingNextStep) {
         this.outbox.push({ content, source })
         return id
       }
@@ -104,19 +107,19 @@ export class ReactLoopAgent implements Agent {
       return id
     }
 
-    const steering = target === 'next-step' && this.turnOpen
+    const placement: InboxPlacement = target === 'next-step' && this.acceptingNextStep ? 'steering' : 'queued'
     const message: AgentMessage = {
       id,
       content,
       source,
     }
-    if (steering) {
+    if (placement === 'steering') {
       this.outbox.push(message)
     } else {
       this.queued.push({ message, wakeup })
     }
-    emitAgentEvent(this.loopCtx, this, 'agent/inbox/enqueue', message)
-    if (!steering && wakeup) this.kick()
+    emitAgentEvent(this.loopCtx, this, 'agent/inbox/enqueue', message, placement)
+    if (placement === 'queued' && wakeup) this.kick()
     return id
   }
 
@@ -212,6 +215,7 @@ export class ReactLoopAgent implements Agent {
 
     const admission = new AbortController()
     this.abort = admission
+    this.acceptingNextStep = true
     // Claimed admission is part of the running interval: it is cancellable
     // activity, so observers (and their cancel routing) must see it.
     if (!this.busy) {
@@ -253,6 +257,7 @@ export class ReactLoopAgent implements Agent {
       // still owns the slot here and releasing it unconditionally is exact.
       this.abort = undefined
       if (admitted === undefined) {
+        this.acceptingNextStep = false
         // A synchronously aborted admission would otherwise publish idle
         // inside send()'s own synchronous extent, before any post-send
         // subscriber could observe the transition.
@@ -279,6 +284,7 @@ export class ReactLoopAgent implements Agent {
     if (this.abort !== undefined) throw new Error(`agent "${this.id}" is already running`)
     const controller = new AbortController()
     this.abort = controller
+    this.acceptingNextStep = true
     if (!this.busy) {
       this.busy = true
       emitAgentEvent(this.loopCtx, this, 'agent/status', 'running')
@@ -384,6 +390,7 @@ export class ReactLoopAgent implements Agent {
       // Every step-close happens before this point on both success and
       // failure paths (step(), the request-failed branch, the catch), so the
       // finally owes only the turn boundary.
+      this.acceptingNextStep = false
       try {
         if (this.turnOpen) {
           // Re-entrant turn/end listeners must route new input to a later turn.
diff --git a/packages/core/agent-loop/tests/contract-regressions.spec.ts b/packages/core/agent-loop/tests/contract-regressions.spec.ts
index a31ac3369c..1cd6fa9bc5 100644
--- a/packages/core/agent-loop/tests/contract-regressions.spec.ts
+++ b/packages/core/agent-loop/tests/contract-regressions.spec.ts
@@ -4,7 +4,7 @@ import LlmService, { CallId, MessageSource, ProviderRequestId, StreamChunk } fro
 import SessionStore, { Session, SessionEvent, SessionId, TurnEndReason } from '@deepseek-ai/dsh-session'
 import SystemPrompt from '@deepseek-ai/dsh-system-prompt'
 import ToolRegistry, { defineContentToolFixture, type PostToolDecision } from '@deepseek-ai/dsh-tools'
-import AgentRegistry, { type Agent } from '@deepseek-ai/dsh-agent'
+import AgentRegistry, { type Agent, type InboxPlacement } from '@deepseek-ai/dsh-agent'
 import AgentLoop from '@deepseek-ai/dsh-agent-loop'
 import { ReactLoopAgent } from '../src/agent.ts'
 import InvariantService from '@deepseek-ai/dsh-invariants'
@@ -500,9 +500,11 @@ describe('adapter registration, routing, and accepted-input ownership', () => {
 
     const queuedSources: MessageSource[] = []
     const queuedShapes: string[][] = []
-    ctx.on('agent/inbox/enqueue', (_agent, message) => {
+    const placements: InboxPlacement[] = []
+    ctx.on('agent/inbox/enqueue', (_agent, message, placement) => {
       queuedSources.push(message.source)
       queuedShapes.push(Object.keys(message).sort())
+      placements.push(placement)
     })
 
     send(agent, 'go') // no explicit source → default {kind:'user'} must be visible
@@ -516,6 +518,7 @@ describe('adapter registration, routing, and accepted-input ownership', () => {
       ['content', 'id', 'source'],
       ['content', 'id', 'source'],
     ])
+    expect(placements).toEqual(['queued', 'steering'])
     // The drain appends the durable steering/message with the caller's source
     // intact — the log, not a transient emit, is where consumers read it.
     const steeringSources = agent.session.events.flatMap(e => e.type === 'steering/message' ? [e.data.source] : [])
diff --git a/packages/core/agent-loop/tests/interception.spec.ts b/packages/core/agent-loop/tests/interception.spec.ts
index abf512ab3c..0e690ab8ae 100644
--- a/packages/core/agent-loop/tests/interception.spec.ts
+++ b/packages/core/agent-loop/tests/interception.spec.ts
@@ -4,7 +4,7 @@ import LlmService, { CallId } from '@deepseek-ai/dsh-llm'
 import SessionStore, { SessionId, type SessionEvent, type TurnEndReason } from '@deepseek-ai/dsh-session'
 import SystemPrompt from '@deepseek-ai/dsh-system-prompt'
 import ToolRegistry, { defineContentToolFixture, type PostToolDecision, type PreToolDecision } from '@deepseek-ai/dsh-tools'
-import AgentRegistry, { type Agent, type PromptDecision, type SessionStartSource } from '@deepseek-ai/dsh-agent'
+import AgentRegistry, { type Agent, type InboxPlacement, type PromptDecision, type SessionStartSource } from '@deepseek-ai/dsh-agent'
 
 import AgentLoop from '@deepseek-ai/dsh-agent-loop'
 import { MockAdapter, textResponse, toolCallResponse } from './mock-adapter.ts'
@@ -164,6 +164,95 @@ describe('agent/prompt-submit', () => {
     expect(reasons).toEqual([])
   })
 
+  it('stages inject and steer during admission for the admitted turn', async () => {
+    const adapter = new MockAdapter([textResponse('ok')])
+    const ctx = await harness(adapter)
+    const agent = ctx.agentLoop.create(SessionId('admission-outbox'), { provider: 'mock', model: 'mock' })
+    const entered = Promise.withResolvers<undefined>()
+    const decision = Promise.withResolvers<PromptDecision>()
+    const placements: InboxPlacement[] = []
+    ctx.on('agent/prompt-submit', async () => {
+      entered.resolve(undefined)
+      return decision.promise
+    })
+    ctx.on('agent/inbox/enqueue', (subject, _message, placement) => {
+      if (subject === agent) placements.push(placement)
+    })
+
+    const idle = waitForIdle(ctx, agent)
+    send(agent, 'admitted prompt')
+    await entered.promise
+    expect(agent.status).toBe('running')
+    expect(events(agent).some(event => event.type === 'turn/start')).toBe(false)
+
+    agent.inject({
+      content: [{ type: 'text', text: 'attached context' }],
+      source: { kind: 'plugin', plugin: 'test' },
+    })
+    agent.steer({ content: [{ type: 'text', text: 'admission steering' }], source: { kind: 'user' } })
+    expect(events(agent).some(event => event.type === 'user/message')).toBe(false)
+    expect(placements).toEqual(['queued', 'steering'])
+
+    decision.resolve({ kind: 'allow' })
+    await idle
+
+    const staged = events(agent).filter(event =>
+      event.type === 'turn/start' || event.type === 'user/message' || event.type === 'steering/message')
+    expect(staged.map(event => event.type)).toEqual([
+      'turn/start',
+      'user/message',
+      'user/message',
+      'steering/message',
+    ])
+    expect(staged[1]?.type === 'user/message' && staged[1].data.content)
+      .toEqual([{ type: 'text', text: 'admitted prompt' }])
+    expect(staged[2]?.type === 'user/message' && staged[2].data.content)
+      .toEqual([{ type: 'text', text: 'attached context' }])
+    expect(staged[3]?.type === 'steering/message' && staged[3].data.content)
+      .toEqual([{ type: 'text', text: 'admission steering' }])
+    const request = JSON.stringify(adapter.requests[0]?.messages)
+    expect(request).toContain('admitted prompt')
+    expect(request).toContain('attached context')
+    expect(request).toContain('admission steering')
+  })
+
+  it('keeps admission-time outbox input staged when admission is blocked', async () => {
+    const adapter = new MockAdapter([textResponse('retried')])
+    const ctx = await harness(adapter)
+    const agent = ctx.agentLoop.create(SessionId('blocked-admission-outbox'), { provider: 'mock', model: 'mock' })
+    const entered = Promise.withResolvers<undefined>()
+    const decision = Promise.withResolvers<PromptDecision>()
+    ctx.on('agent/prompt-submit', async () => {
+      entered.resolve(undefined)
+      return decision.promise
+    })
+
+    const blockedIdle = waitForIdle(ctx, agent)
+    send(agent, 'blocked prompt')
+    await entered.promise
+    agent.inject({
+      content: [{ type: 'text', text: 'staged context' }],
+      source: { kind: 'plugin', plugin: 'test' },
+    })
+    agent.steer({ content: [{ type: 'text', text: 'staged steering' }], source: { kind: 'user' } })
+    decision.resolve({ kind: 'block', reason: 'policy' })
+    await blockedIdle
+
+    expect(events(agent)).toEqual([])
+    expect(adapter.requests).toEqual([])
+
+    const retryIdle = waitForIdle(ctx, agent)
+    agent.retry()
+    await retryIdle
+
+    const staged = events(agent).filter(event =>
+      event.type === 'user/message' || event.type === 'steering/message')
+    expect(staged.map(event => event.type)).toEqual(['user/message', 'steering/message'])
+    expect(JSON.stringify(adapter.requests[0]?.messages)).not.toContain('blocked prompt')
+    expect(JSON.stringify(adapter.requests[0]?.messages)).toContain('staged context')
+    expect(JSON.stringify(adapter.requests[0]?.messages)).toContain('staged steering')
+  })
+
   it('adjacent blocked and allowed prompts keep independent turn outcomes', async () => {
     const adapter = new MockAdapter([textResponse('ran once')])
     const ctx = await harness(adapter)
diff --git a/packages/core/agent/src/types.ts b/packages/core/agent/src/types.ts
index ac2350dafe..f59f0d92fb 100644
--- a/packages/core/agent/src/types.ts
+++ b/packages/core/agent/src/types.ts
@@ -29,11 +29,15 @@ export interface AgentOptions {
 /**
  * Which inbox queue a {@link Agent.send} item joins:
  * - `next-turn` — the item becomes its own turn, claimed at a turn boundary.
- * - `next-step` — the item joins the active turn between steps as steering,
- *   or, when no turn is active, is promoted per its `wakeup` flag.
+ * - `next-step` — during prompt admission or an open turn, the item stages for
+ *   the next safe step boundary; otherwise it is promoted per its `wakeup`
+ *   flag.
  */
 export type SendTarget = 'next-turn' | 'next-step'
 
+/** Resolved inbox placement reported when an accepted message is enqueued. */
+export type InboxPlacement = 'queued' | 'steering'
+
 /**
  * Options for the unified {@link Agent.send} primitive over the
  * (`target` × `wakeup`) matrix. Named presets: {@link Agent.followup}
@@ -153,12 +157,13 @@ export interface Agent {
    * - `next-turn` queues an item that becomes the sole ordinary message of its
    *   own FIFO-ordered turn; `wakeup:true` wakes a
    *   parked driver, while `wakeup:false` queues without waking.
-   * - `next-step` with `wakeup:true` submits steering into the active turn
-   *   (idle falls back to a woken `next-turn`).
+   * - `next-step` with `wakeup:true` stages steering during prompt admission
+   *   or an open turn; outside that window it falls back to a woken
+   *   `next-turn`.
    * - `next-step` with `wakeup:false` injects durable model-facing context
-   *   without running the model: an open turn stages it for the next safe log
-   *   position, while an idle injection appends it immediately without opening
-   *   a turn.
+   *   without running the model: admission or an open turn stages it for the
+   *   next safe log position, while an injection outside that window appends
+   *   immediately without opening a turn.
    * @param input - model-facing content and its producer provenance.
    * @param options - target queue and wakeup decision.
    * @returns the accepted message's {@link AgentMessageId}, stable across its `agent/inbox/*` events.
@@ -189,12 +194,13 @@ export interface Agent {
   followup(input: UserMessageData): AgentMessageId
 
   /**
-   * Submit steering into the running turn — the `next-step`/wakeup preset of
-   * {@link send}. An open turn records it at the next steering checkpoint before
-   * a request or stop decision. If the turn fails before that boundary, the
-   * remainder stays staged without waking the agent; retry or a later prompt
-   * takes it. Idle steering falls back to a woken follow-up turn, while
-   * cancellation or disposal may discard pending steering.
+   * Submit steering during prompt admission or an open turn — the
+   * `next-step`/wakeup preset of {@link send}. It stages for the next steering
+   * checkpoint before a request or stop decision. If the activity fails before
+   * that boundary, the remainder stays staged without waking the agent; retry
+   * or a later prompt takes it. Outside that window steering falls back to a
+   * woken follow-up turn, while cancellation or disposal may discard pending
+   * steering.
    * @param input - steering content and its producer provenance.
    * @returns the accepted message's {@link AgentMessageId}.
    */
@@ -202,9 +208,9 @@ export interface Agent {
 
   /**
    * Append model-facing context without running the model — the
-   * `next-step`/no-wakeup preset of {@link send}. An open-turn injection stages
-   * at the next safe log position; an idle injection appends immediately
-   * without opening a turn.
+   * `next-step`/no-wakeup preset of {@link send}. Admission or an open turn
+   * stages it at the next safe log position; outside that window it appends
+   * immediately without opening a turn.
    * @param input - injected context and its producer provenance.
    * @returns the accepted message's {@link AgentMessageId}.
    */
@@ -253,13 +259,16 @@ declare module 'cordis' {
      */
     'agent/status'(this: Scoped<Agent>, agent: Agent, status: AgentStatus): void
     /**
-     * An item entered the queued or steering inbox.
+     * An item entered the queued or steering inbox. `placement` is the
+     * acceptance-time routing result; listeners must not reconstruct it from
+     * later agent or session state.
      * @param agent - the owning agent.
      * @param message - accepted content, source, and correlation identity.
+     * @param placement - resolved queued or steering placement.
      * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode emit
      */
-    'agent/inbox/enqueue'(this: Scoped<Agent>, agent: Agent, message: AgentMessage): void
+    'agent/inbox/enqueue'(this: Scoped<Agent>, agent: Agent, message: AgentMessage, placement: InboxPlacement): void
     /**
      * The driver claimed one item out of the inbox: a queued item at a turn
      * boundary, or steering drained between steps. Fires after the item leaves
diff --git a/packages/core/agent/tests/invariant.spec.ts b/packages/core/agent/tests/invariant.spec.ts
index 8b5e6ae7d7..d95d97ea32 100644
--- a/packages/core/agent/tests/invariant.spec.ts
+++ b/packages/core/agent/tests/invariant.spec.ts
@@ -52,8 +52,8 @@ describe('agent inbox invariants', () => {
     const agent = mockAgent('i1')
     const at = scopeTarget(agent, agent)
     expect(() => {
-      ctx.emit(at, 'agent/inbox/enqueue', agent, info())
-      ctx.emit(at, 'agent/inbox/enqueue', agent, info())
+      ctx.emit(at, 'agent/inbox/enqueue', agent, info(), 'queued')
+      ctx.emit(at, 'agent/inbox/enqueue', agent, info(), 'steering')
       ctx.emit(at, 'agent/inbox/dequeue', agent, info())
       ctx.emit(at, 'agent/inbox/discard', agent, [info()])
     }).not.toThrow()
@@ -70,7 +70,7 @@ describe('agent inbox invariants', () => {
     const ctx = await setup()
     const agent = mockAgent('i3')
     const at = scopeTarget(agent, agent)
-    ctx.emit(at, 'agent/inbox/enqueue', agent, info())
+    ctx.emit(at, 'agent/inbox/enqueue', agent, info(), 'queued')
     expect(() => { ctx.emit(at, 'agent/inbox/discard', agent, [info(), info()]) })
       .toThrow(/dropped 2 items but only 1 were outstanding/)
   })
diff --git a/packages/core/scope/tests/invariant.spec.ts b/packages/core/scope/tests/invariant.spec.ts
index e0acb2809c..e94a061cf6 100644
--- a/packages/core/scope/tests/invariant.spec.ts
+++ b/packages/core/scope/tests/invariant.spec.ts
@@ -41,7 +41,7 @@ describe('scoped-dispatch invariants', () => {
       'agent/created': [agent],
       'agent/disposed': [agent],
       'agent/status': [agent, 'idle'],
-      'agent/inbox/enqueue': [agent, { id: AgentMessageId('m'), content: [], source: { kind: 'user' } }],
+      'agent/inbox/enqueue': [agent, { id: AgentMessageId('m'), content: [], source: { kind: 'user' } }, 'queued'],
       'agent/inbox/dequeue': [agent, { id: AgentMessageId('m'), content: [], source: { kind: 'user' } }],
       'agent/inbox/discard': [agent, []],
       'agent/cancel-requested': [agent, { kind: 'user' }],
diff --git a/packages/host/apiproxy/src/api-proxy.ts b/packages/host/apiproxy/src/api-proxy.ts
index bb962ab84c..0ac45fa588 100644
--- a/packages/host/apiproxy/src/api-proxy.ts
+++ b/packages/host/apiproxy/src/api-proxy.ts
@@ -380,7 +380,7 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
    * `agent/inbox/dequeue` OR `agent/inbox/discard` (the inbox contract), so
    * the mirror needs no consumption heuristics or sweeps beyond disposal.
    */
-  const queuedMirror = new Map<SessionId, Map<AgentMessageId, AgentMessage>>()
+  const queuedMirror = new Map<SessionId, Map<AgentMessageId, { message: AgentMessage; steering: boolean }>>()
   ctx.effect(() => {
     const retire = (agent: Agent, id: AgentMessageId): void => {
       const entries = queuedMirror.get(agent.id)
@@ -389,11 +389,21 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
       if (entries.size === 0) queuedMirror.delete(agent.id)
     }
     const disposers = [
-      ctx.on('agent/inbox/enqueue', (agent: Agent, message: AgentMessage) => {
+      ctx.on('agent/inbox/enqueue', (agent: Agent, message: AgentMessage, placement) => {
         let entries = queuedMirror.get(agent.id)
-        if (entries === undefined) queuedMirror.set(agent.id, entries = new Map<AgentMessageId, AgentMessage>())
-        entries.set(message.id, message)
-        broadcast({ type: 'session/queued', sessionId: agent.id, content: message.content, source: message.source })
+        if (entries === undefined) {
+          entries = new Map<AgentMessageId, { message: AgentMessage; steering: boolean }>()
+          queuedMirror.set(agent.id, entries)
+        }
+        const steering = placement === 'steering'
+        entries.set(message.id, { message, steering })
+        broadcast({
+          type: 'session/queued',
+          sessionId: agent.id,
+          content: message.content,
+          source: message.source,
+          steering,
+        })
       }),
       ctx.on('agent/inbox/dequeue', (agent: Agent, message: AgentMessage) => {
         retire(agent, message.id)
@@ -929,7 +939,13 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
         // queue view from these alone.
         for (const [sessionId, entries] of queuedMirror) {
           for (const entry of entries.values()) {
-            queue.push(frame({ type: 'session/queued', sessionId, content: entry.content, source: entry.source }))
+            queue.push(frame({
+              type: 'session/queued',
+              sessionId,
+              content: entry.message.content,
+              source: entry.message.source,
+              steering: entry.steering,
+            }))
           }
         }
         // Per-session open-call table for result-view pairing. Bounded by the
diff --git a/packages/host/apiproxy/src/api/events.schema.ts b/packages/host/apiproxy/src/api/events.schema.ts
index 4a0d88fa38..973db5a91e 100644
--- a/packages/host/apiproxy/src/api/events.schema.ts
+++ b/packages/host/apiproxy/src/api/events.schema.ts
@@ -36,7 +36,7 @@ export const muxFrameSchema = z.discriminatedUnion('type', [
   z.object({ type: z.literal('question/requested'), sessionId: sessionIdSchema, questions: z.array(askUserQuestionItemSchema).min(1) }),
   z.object({ type: z.literal('question/resolved'), sessionId: sessionIdSchema, questionRpcId: rpcIdSchema, outcome: z.union([z.literal('answered'), z.literal('cancelled')]) }),
   // content/source reuse the wide passthroughs (both are merge-extensible in core).
-  z.object({ type: z.literal('session/queued'), sessionId: sessionIdSchema, content: z.array(contentBlockSchema), source: z.looseObject({ kind: z.string() }) }),
+  z.object({ type: z.literal('session/queued'), sessionId: sessionIdSchema, content: z.array(contentBlockSchema), source: z.looseObject({ kind: z.string() }), steering: z.boolean() }),
   z.object({ type: z.literal('stream/error'), error: rpcErrorSchema }),
 ]) as unknown as z.ZodType<MuxFrame>
 
diff --git a/packages/host/apiproxy/src/api/events.ts b/packages/host/apiproxy/src/api/events.ts
index debb1750c3..804f689f97 100644
--- a/packages/host/apiproxy/src/api/events.ts
+++ b/packages/host/apiproxy/src/api/events.ts
@@ -69,10 +69,12 @@ export type MuxFrame =
    * host replays the current queue snapshot for every attached session (same
    * refresh-recovery baseline as pending questions); queue clearing on cancel
    * has no dedicated frame — clients fold it from the status flip.
-   * source carries the prompt's rpcId when the message came over this wire
-   * (the client's provisional-echo reconciliation key).
+   * `steering` is the host's acceptance-time queue classification and remains
+   * authoritative in reconnect snapshots. `source` carries the prompt's rpcId
+   * when the message came over this wire (the client's provisional-echo
+   * reconciliation key).
    */
-  | { type: 'session/queued'; sessionId: SessionId; content: ContentBlock[]; source: MessageSource }
+  | { type: 'session/queued'; sessionId: SessionId; content: ContentBlock[]; source: MessageSource; steering: boolean }
   | { type: 'stream/error'; error: RpcError }
 
 /**
diff --git a/packages/host/apiproxy/tests/api-proxy-commands.spec.ts b/packages/host/apiproxy/tests/api-proxy-commands.spec.ts
index 0483f3837e..480f821b95 100644
--- a/packages/host/apiproxy/tests/api-proxy-commands.spec.ts
+++ b/packages/host/apiproxy/tests/api-proxy-commands.spec.ts
@@ -258,20 +258,20 @@ describe('session/queued frames', () => {
 
     const queued = inboxMessage('m-1', 'queued prompt')
     const steering = inboxMessage('m-2', 'queued prompt')
-    ctx.emit('agent/inbox/enqueue', agent, queued)
-    ctx.emit('agent/inbox/enqueue', agent, steering)
+    ctx.emit('agent/inbox/enqueue', agent, queued, 'queued')
+    ctx.emit('agent/inbox/enqueue', agent, steering, 'steering')
 
     const liveFrames = (await liveCollected).filter(f => f.type === 'session/queued')
     expect(liveFrames).toEqual([
-      { type: 'session/queued', sessionId: agent.id, content: queued.content, source: { kind: 'user' } },
-      { type: 'session/queued', sessionId: agent.id, content: steering.content, source: { kind: 'user' } },
+      { type: 'session/queued', sessionId: agent.id, content: queued.content, source: { kind: 'user' }, steering: false },
+      { type: 'session/queued', sessionId: agent.id, content: steering.content, source: { kind: 'user' }, steering: true },
     ])
 
     // A fresh mux connection replays the still-pending entries as its baseline.
     const replay = new AbortController()
     const replayFrames = await collect<MuxFrame>(
       api.events.mux({ rpcId: RpcId('t-mux-replay'), payload: {} }, replay.signal), 3, replay)
-    expect(replayFrames.filter(f => f.type === 'session/queued')).toHaveLength(2)
+    expect(replayFrames.filter(f => f.type === 'session/queued')).toEqual(liveFrames)
   })
 
   it('retires mirror entries on their terminal dequeue', async () => {
@@ -280,8 +280,8 @@ describe('session/queued frames', () => {
     const agent = stubAgent(ctx)
     const queued = inboxMessage('m-3', 'x')
     const steering = inboxMessage('m-4', 'x', 'r-1')
-    ctx.emit('agent/inbox/enqueue', agent, queued)
-    ctx.emit('agent/inbox/enqueue', agent, steering)
+    ctx.emit('agent/inbox/enqueue', agent, queued, 'queued')
+    ctx.emit('agent/inbox/enqueue', agent, steering, 'steering')
     ctx.emit('agent/inbox/dequeue', agent, queued)
     ctx.emit('agent/inbox/dequeue', agent, steering)
 
@@ -297,8 +297,8 @@ describe('session/queued frames', () => {
     const agent = stubAgent(ctx)
     const doomed = inboxMessage('m-5', 'doomed')
     const survivor = inboxMessage('m-6', 'survivor')
-    ctx.emit('agent/inbox/enqueue', agent, doomed)
-    ctx.emit('agent/inbox/enqueue', agent, survivor)
+    ctx.emit('agent/inbox/enqueue', agent, doomed, 'queued')
+    ctx.emit('agent/inbox/enqueue', agent, survivor, 'queued')
     ctx.emit('agent/inbox/discard', agent, [doomed])
 
     const abort = new AbortController()
diff --git a/packages/host/apiproxy/tests/rpc-schemas.spec.ts b/packages/host/apiproxy/tests/rpc-schemas.spec.ts
index 032be04e44..5002f8b857 100644
--- a/packages/host/apiproxy/tests/rpc-schemas.spec.ts
+++ b/packages/host/apiproxy/tests/rpc-schemas.spec.ts
@@ -248,8 +248,8 @@ describe('events frame schemas', () => {
       { type: 'approval/resolved', sessionId: 's', approvalId: 'a', outcome: 'allowed-once' },
       { type: 'question/requested', sessionId: 's', questions: [{ id: 'q', question: 'Q?', options: [{ label: 'L' }], multiSelect: true }] },
       { type: 'question/resolved', sessionId: 's', questionRpcId: 'r', outcome: 'answered' },
-      { type: 'session/queued', sessionId: 's', content: [{ type: 'text', text: 'queued prompt' }], source: { kind: 'user', rpcId: 'r9' } },
-      { type: 'session/queued', sessionId: 's', content: [{ type: 'text', text: 'steer' }], source: { kind: 'user' } },
+      { type: 'session/queued', sessionId: 's', content: [{ type: 'text', text: 'queued prompt' }], source: { kind: 'user', rpcId: 'r9' }, steering: false },
+      { type: 'session/queued', sessionId: 's', content: [{ type: 'text', text: 'steer' }], source: { kind: 'user' }, steering: true },
       { type: 'stream/error', error: { code: 'internal', message: 'm', details: {} } },
     ]
     for (const frame of frames) expect(muxFrameSchema.parse(frame)).toMatchObject({ type: frame.type })
@@ -270,7 +270,8 @@ describe('events frame schemas', () => {
 
   it('rejects a queued frame missing its members', () => {
     expect(() => muxFrameSchema.parse({ type: 'session/queued', sessionId: 's', content: 'x', source: { kind: 'user' } })).toThrow()
-    expect(() => muxFrameSchema.parse({ type: 'session/queued', sessionId: 's', content: [], source: {} })).toThrow()
+    expect(() => muxFrameSchema.parse({ type: 'session/queued', sessionId: 's', content: [], source: { kind: 'user' } })).toThrow()
+    expect(() => muxFrameSchema.parse({ type: 'session/queued', sessionId: 's', content: [], source: {}, steering: false })).toThrow()
   })
 
   it('accepts every host frame branch', () => {
diff --git a/packages/ui/tui/src/index.ts b/packages/ui/tui/src/index.ts
index 35044b668f..ba31c7ca24 100644
--- a/packages/ui/tui/src/index.ts
+++ b/packages/ui/tui/src/index.ts
@@ -2907,10 +2907,8 @@ export function createTuiChat(
       agent.followup({ content, source: { kind: 'user' } })
       return
     }
-    // Idle: the snapshot rides the prompt's own admission transaction
-    // (PromptDecision.additionalContexts), so a blocking hook discards the
-    // prompt and its attached context together instead of stranding the
-    // snapshot in history for the next unrelated prompt.
+    // Idle: the snapshot rides the prompt's admission transaction so a
+    // blocking hook discards both together.
     let cleanedUp = false
     const cleanup = (): void => {
       // Each trigger detaches both listeners, so a second call needs a
diff --git a/packages/ui/tui/tests/tui.spec.ts b/packages/ui/tui/tests/tui.spec.ts
index bf84a5ebbf..0929f3fa99 100644
--- a/packages/ui/tui/tests/tui.spec.ts
+++ b/packages/ui/tui/tests/tui.spec.ts
@@ -1384,7 +1384,7 @@ describe('pi-tui chat lifecycle and transcript', () => {
     // A steering queue for a different agent never touches this status line.
     const other = { ...result.agent, id: SessionId('other') } as unknown as Agent
     result.terminal.output = ''
-    result.ctx.emit('agent/inbox/enqueue', other, { id: AgentMessageId('stub'), content: [{ type: 'text', text: 'elsewhere' }], source: { kind: 'user' } })
+    result.ctx.emit('agent/inbox/enqueue', other, { id: AgentMessageId('stub'), content: [{ type: 'text', text: 'elsewhere' }], source: { kind: 'user' } }, 'queued')
     await tick()
     expect(result.terminal.output).not.toContain('queued')
 
@@ -1474,7 +1474,7 @@ describe('pi-tui chat lifecycle and transcript', () => {
     // A live event before the turn runs has no status controller to move.
     const idle = await setup()
     // Inbox notifications do not affect the status phase while idle.
-    idle.ctx.emit('agent/inbox/enqueue', idle.agent, { id: AgentMessageId('stub'), content: [{ type: 'text', text: 'early' }], source: { kind: 'user' } })
+    idle.ctx.emit('agent/inbox/enqueue', idle.agent, { id: AgentMessageId('stub'), content: [{ type: 'text', text: 'early' }], source: { kind: 'user' } }, 'queued')
     idle.session.append('tool/call', { turn: 1, step: 0, callId: 'pre' as never, name: 'bash', arguments: '{}' })
     await tick()
     expect(idle.terminal.output).not.toContain('Executing tools')