fix(native-chat): a long reply keeps its Working bar and Stop after a reload, from the host's turn

mobile/src/session/mobile-structured-agent-session-cancel.ts

@@ -1,7 +1,7 @@
 import type { AgentSessionCancelResult } from '../../../src/shared/agent-session-wire'
 import type { AgentJournalRenderItem } from '../../../src/shared/agent-session-journal-types'
 import type { StructuredAgentSessionState } from '../../../src/shared/structured-agent-session-reducer'
-import { activeStructuredAgentSessionTurnId } from '../../../src/shared/structured-agent-session-live-turn'
+import { runningStructuredAgentSessionTurnId } from '../../../src/shared/structured-agent-session-live-turn'
 import type { RpcClient } from '../transport/rpc-client'
 import {
   requestStructuredAgentSessionMutation,
@@ -37,7 +37,7 @@ export async function requestMobileStructuredAgentSessionCancel(args: {
 }): Promise<boolean> {
   const { client, enabled, inFlight, onSendError, sessionId, stateRef } = args
   const current = stateRef.current
-  const turnId = activeStructuredAgentSessionTurnId(current.items)
+  const turnId = runningStructuredAgentSessionTurnId(current)
   if (!client || !sessionId || !enabled || current.fence === null || !turnId) {
     onSendError('Stop not sent')
     return false

mobile/src/session/use-mobile-native-chat-turn-disclosure.test.tsx

@@ -761,4 +761,47 @@ describe('useMobileNativeChatTurnDisclosure', () => {
     expect(rows.map((row) => row.activeTurnIsWorking)).toEqual([false, false, true])
     expect(rows[0].turnStatus?.workedSeconds).toBe(4)
   })
+
+  it('draws the live bar on a turn whose record and opening message are not loaded', () => {
+    // The newest rows of a long turn; its record is above the page, named only by the host.
+    const items: AgentJournalRenderItem[] = ['a300', 'a301'].map((itemId, index) => ({
+      itemId,
+      revision: 0,
+      sequence: 300 + index,
+      observedAt: 300 + index,
+      body: { kind: 'message', role: 'assistant', blocks: [{ type: 'text', text: itemId }] },
+      turnScope: { kind: 'turn', turnItemId: 'turn-record' }
+    }))
+    const messages: NativeChatMessage[] = items.map((item) => ({
+      ...userMessage(item.itemId),
+      role: 'assistant'
+    }))
+    const rowsWith = (latestTurn: NativeChatTurnJournal['latestTurn']) => {
+      act(() => {
+        renderer = create(
+          createElement(Harness, {
+            messages,
+            enabled: true,
+            workingStartedAt: 1_000,
+            turnJournal: { items, submissions: [], latestTurn }
+          })
+        )
+      })
+      const disclosure = renderer!.root.findByType('result').props.disclosure
+      const rows = messages.map((message, index) => disclosure.resolveRow(index, message))
+      act(() => renderer?.unmount())
+      return rows
+    }
+
+    const hosted = rowsWith({
+      itemId: 'turn-record',
+      observedAt: 1,
+      turn: { turnId: 'turn-1', state: 'running', startedAt: 1_000, userItemId: 'user-1' }
+    })
+    expect(hosted[0]?.turnStatus).toMatchObject({ startedAt: 1_000 })
+    expect(hosted.map((row) => row.activeTurnIsWorking)).toEqual([true, true])
+
+    // From the loaded rows alone, nothing names the turn, so no bar draws.
+    expect(rowsWith(undefined).map((row) => row.turnStatus)).toEqual([null, null])
+  })
 })

mobile/src/session/use-mobile-structured-agent-session-prompt-cancel.test.tsx

@@ -224,6 +224,49 @@ describe('mobile structured prompt cancellation', () => {
     )
   })
 
+  it("stops the host's running turn when its record is not loaded", async () => {
+    state = {
+      ...state,
+      hasOlder: true,
+      items: [pendingApproval()],
+      latestTurn: {
+        itemId: 'turn-status',
+        observedAt: 1,
+        turn: { turnId: 'turn-1', state: 'running', startedAt: 1 }
+      }
+    }
+    act(() => {
+      renderer = create(createElement(Harness, { promptCancelSupported: true }))
+    })
+    expect(hook.isWorking).toBe(true)
+    await act(async () => {
+      expect(await hook.cancelPrompt()).toBe(true)
+    })
+    expect(mocks.sendRequest).toHaveBeenCalledWith(
+      'agentSession.cancel',
+      expect.objectContaining({
+        turnId: 'turn-1',
+        prompt: { itemId: 'approval-1', expectedRevision: 4 }
+      }),
+      expect.any(Object)
+    )
+  })
+
+  it('reads a turn the host ended as ended, though its running row is still loaded', () => {
+    state = {
+      ...state,
+      latestTurn: {
+        itemId: 'turn-status',
+        observedAt: 1,
+        turn: { turnId: 'turn-1', state: 'completed', startedAt: 1, completedAt: 2 }
+      }
+    }
+    act(() => {
+      renderer = create(createElement(Harness, { promptCancelSupported: true }))
+    })
+    expect(hook.turnId).toBeNull()
+  })
+
   it('uses the rendered prompt identity when the journal changes before tap', async () => {
     act(() => {
       renderer = create(createElement(Harness, { promptCancelSupported: true }))
@@ -243,4 +286,28 @@ describe('mobile structured prompt cancellation', () => {
       expect.any(Object)
     )
   })
+
+  it("names the host's running turn for a plain Stop when its record is not loaded", async () => {
+    state = {
+      ...state,
+      hasOlder: true,
+      items: [],
+      latestTurn: {
+        itemId: 'turn-status',
+        observedAt: 1,
+        turn: { turnId: 'turn-1', state: 'running' }
+      }
+    }
+    act(() => {
+      renderer = create(createElement(Harness, { promptCancelSupported: true }))
+    })
+    expect(hook.turnId).toBe('turn-1')
+    await act(async () => {
+      hook.cancel()
+    })
+    const call = mocks.sendRequest.mock.calls.find(([method]) => method === 'agentSession.cancel')
+    expect(call).toBeDefined()
+    expect(call?.[1]).toMatchObject({ turnId: 'turn-1' })
+    expect(call?.[1]).not.toHaveProperty('prompt')
+  })
 })

mobile/src/session/use-mobile-structured-agent-session.ts

@@ -7,8 +7,8 @@ import { TUI_AGENT_DISPLAY_NAMES } from '../../../src/shared/tui-agent-display-n
 import { isStructuredAgentSessionMainAgentWorking } from '../../../src/shared/structured-agent-session-main-agent-working'
 import { isFinalAgentSessionReadRefusal } from '../../../src/shared/structured-agent-session-read-refusal'
 import {
-  activeStructuredAgentSessionTurnId,
-  isStructuredAgentSessionThinking
+  isStructuredAgentSessionThinking,
+  runningStructuredAgentSessionTurnId
 } from '../../../src/shared/structured-agent-session-live-turn'
 import { selectStructuredAgentTurnActivity } from '../../../src/shared/native-chat-turn-activity'
 import {
@@ -177,14 +177,14 @@ export function useMobileStructuredAgentSession(args: {
       }),
     [transcriptItems, state.submissions]
   )
-  const turnId = activeStructuredAgentSessionTurnId(state.items)
+  const turnId = runningStructuredAgentSessionTurnId(state)
   const turnTiming = useMobileStructuredAgentTurnTiming(
     { ...state, items: transcriptItems },
     turnId
   )
   const activityText =
     selectStructuredAgentTurnActivity(state.items, turnId, state.activity)?.text ?? null
-  const thinking = isStructuredAgentSessionThinking(state.items)
+  const thinking = isStructuredAgentSessionThinking(state)
   const turnIndicator = useMemo(() => ({ thinking, activityText }), [thinking, activityText])
   const status = state.status === 'idle' ? 'idle' : state.status
   const approvalPrompt = useMemo(

mobile/src/session/use-mobile-structured-agent-turn-timing.ts

@@ -4,6 +4,7 @@ import type {
   AgentJournalSubmission
 } from '../../../src/shared/agent-session-journal-types'
 import type { NativeChatSettledTurns } from '../../../src/shared/native-chat-turn-status'
+import type { AgentSessionLatestTurn } from '../../../src/shared/agent-session-wire'
 import type { NativeChatTurnJournal } from '../../../src/shared/native-chat-turn-membership'
 import type { StructuredAgentHostClock } from '../../../src/shared/structured-agent-session-reducer'
 import { selectStructuredAgentTurnBars } from '../../../src/shared/structured-agent-session-turn-timing'
@@ -19,10 +20,12 @@ export function useMobileStructuredAgentTurnTiming(
   {
     items,
     submissions,
+    latestTurn,
     hostClock
   }: {
     items: readonly AgentJournalRenderItem[]
     submissions: readonly AgentJournalSubmission[]
+    latestTurn?: AgentSessionLatestTurn | null
     hostClock?: StructuredAgentHostClock | null
   },
   turnId: string | null
@@ -33,10 +36,13 @@ export function useMobileStructuredAgentTurnTiming(
   workingStartedAt: number | null
 } {
   const { settledTurns, runningTiming } = useMemo(
-    () => selectStructuredAgentTurnBars(items, submissions, turnId),
-    [items, submissions, turnId]
+    () => selectStructuredAgentTurnBars(items, submissions, turnId, latestTurn),
+    [items, submissions, turnId, latestTurn]
+  )
+  const turnJournal = useMemo(
+    () => ({ items, submissions, latestTurn }),
+    [items, submissions, latestTurn]
   )
-  const turnJournal = useMemo(() => ({ items, submissions }), [items, submissions])
   const [latch, setLatch] = useState<StructuredAgentTurnClockLatch | null>(null)
   // Stamp during render (React's derive-from-props pattern) so the first paint of
   // a new turn already counts from the right instant.

mobile/src/session/use-mobile-structured-send-with-outcome.ts

@@ -4,7 +4,7 @@
 // host advertises the queue and no pending prompt is one this build cannot answer.
 
 import { useCallback } from 'react'
-import { activeStructuredAgentSessionTurnId } from '../../../src/shared/structured-agent-session-live-turn'
+import { runningStructuredAgentSessionTurnId } from '../../../src/shared/structured-agent-session-live-turn'
 import { pendingPromptsAllUnanswerableHere } from '../../../src/shared/agent-session-approval-subject'
 import {
   structuredAgentSessionSendBody,
@@ -95,7 +95,7 @@ export function useMobileStructuredSendWithOutcome(args: {
           ...controller
         },
         canRun: () =>
-          !activeStructuredAgentSessionTurnId(stateRef.current.items) &&
+          !runningStructuredAgentSessionTurnId(stateRef.current) &&
           !stateRef.current.items.some(
             (item) => pendingStructuredApproval(item) || pendingStructuredQuestion(item)
           ),

src/main/codex/codex-structured-journal-subagent-readers.test.ts

@@ -163,7 +163,7 @@ describe("a Codex subagent's rows on the parent's surfaces", () => {
       summary: ['Reading the diff']
     })
 
-    expect(isStructuredAgentSessionThinking(await items())).toBe(false)
+    expect(isStructuredAgentSessionThinking({ items: await items() })).toBe(false)
   })
 
   it("does not show the child's compaction as the parent's activity line", async () => {

src/main/native-chat/agent-session-wire/agent-session-history-page.ts

@@ -9,6 +9,7 @@
 
 import { agentJournalSubmissionKey } from '../../../shared/agent-session-journal-item-key'
 import { isRootAgentJournalItem } from '../../../shared/agent-session-journal-producer'
+import { latestStructuredAgentSessionTurn } from '../../../shared/structured-agent-session-live-turn'
 import type {
   AgentJournalCursor,
   AgentJournalRenderItem,
@@ -21,6 +22,7 @@ import {
   type AgentSessionHistoryPage,
   type AgentSessionHistoryRequest,
   type AgentSessionHistoryResult,
+  type AgentSessionLatestTurn,
   type AgentSessionSubagentRosterEntry
 } from '../../../shared/agent-session-wire'
 import type { AgentSessionJournal } from '../agent-session-journal/journal-store'
@@ -308,6 +310,20 @@ function buildPage(input: {
     liveCursor: input.snapshot.cursor,
     hasOlder: input.hasOlder,
     hasNewer: input.hasNewer,
-    ...(input.subagentRoster === undefined ? {} : { subagentRoster: input.subagentRoster })
+    ...(input.subagentRoster === undefined ? {} : { subagentRoster: input.subagentRoster }),
+    // From the whole timeline, never the page: a long turn's record sits below any window.
+    latestTurn: snapshotLatestTurn(input.snapshot)
   }
 }
+
+// A catch-up run pages one snapshot many times; its scan back to the turn record is paid once.
+const latestTurnBySnapshot = new WeakMap<AgentJournalSnapshot, AgentSessionLatestTurn | null>()
+
+function snapshotLatestTurn(snapshot: AgentJournalSnapshot): AgentSessionLatestTurn | null {
+  let latest = latestTurnBySnapshot.get(snapshot)
+  if (latest === undefined) {
+    latest = latestStructuredAgentSessionTurn(snapshot.items)
+    latestTurnBySnapshot.set(snapshot, latest)
+  }
+  return latest
+}

src/main/native-chat/agent-session-wire/agent-session-subscriber-catch-up.ts

@@ -93,6 +93,7 @@ export function deliverToSubscriber(
           submissions: page.submissions
         },
         fence: subscriber.fence,
+        ...(page.latestTurn !== undefined ? { latestTurn: page.latestTurn } : {}),
         ...shared
       },
       // On a multi-page catch-up the draft list rides only the final page, or a