diff --git a/src/main/claude/claude-structured-journal-translation.test.ts b/src/main/claude/claude-structured-journal-translation.test.ts
index 7a8ecf54344..faf79a7b15d 100644
--- a/src/main/claude/claude-structured-journal-translation.test.ts
+++ b/src/main/claude/claude-structured-journal-translation.test.ts
@@ -568,7 +568,11 @@ describe('Claude structured journal translation', () => {
 
     translator.handle(message('assistant', 'assistant-thinking', [{ type: 'thinking', thinking }]))
 
-    expect(state.items.at(-1)?.body).toEqual({
+    // The frame also opens the turn it produced in, so pick the reasoning row itself.
+    const reasoning = state.items.find(
+      (item) => item.body.kind === 'message' && item.body.role === 'reasoning'
+    )
+    expect(reasoning?.body).toEqual({
       kind: 'message',
       role: 'reasoning',
       blocks: [
diff --git a/src/main/claude/claude-structured-journal-translation.ts b/src/main/claude/claude-structured-journal-translation.ts
index 8b71149cba2..9e5bfc499b4 100644
--- a/src/main/claude/claude-structured-journal-translation.ts
+++ b/src/main/claude/claude-structured-journal-translation.ts
@@ -10,7 +10,6 @@ import type { ClaudeStructuredSessionEvent } from './claude-structured-session-s
 import {
   claudeMessageBody,
   claudeMessageIdentity,
-  claudeHasReplayContent,
   claudeOutputEnvelope,
   claudeStreamingMessageBody,
   claudeThinkingIdentity,
@@ -39,6 +38,7 @@ import {
 import { ClaudeSubagentRoster } from './claude-subagent-roster'
 import { createClaudeStreamedBlockRegistry } from './claude-streamed-block-identity'
 import { createClaudeStreamedTextCheckpoints } from './claude-streamed-text-checkpoints'
+import { claudeTurnOpenedByFrame } from './claude-turn-opening'
 import {
   claudeTurnEndForResult,
   claudeTurnLifecycleItem,
@@ -189,25 +189,24 @@ export function createClaudeJournalTranslator(
       changed = true
     }
     changed = appendUnmodeledClaudeContent(providerFallback, outputEnvelope, message) || changed
-    if (
-      envelope.role === 'user' &&
-      startsTurn &&
-      claudeHasReplayContent(envelope) &&
-      message.parent_tool_use_id === null
-    ) {
+    const opened = claudeTurnOpenedByFrame({
+      envelope,
+      frame: message,
+      startsTurn,
+      producedContent: changed,
+      hasOpenTurn: currentTurn !== null,
+      observedAt,
+      // A user echo lands on its own message identity, so this is the user row's key.
+      userItemId: agentJournalItemKey(identity)
+    })
+    if (opened) {
       if (currentTurn) {
         // A new turn starting is the only end the previous one gets when its
         // result never arrives; settling it later would sweep THIS turn.
         subagents.settleTurn(groupKeyOf(currentTurn))
         publishLifecycle(currentTurn, { state: 'interrupted', completedAt: observedAt })
       }
-      currentTurn = {
-        sessionId: envelope.sessionId,
-        turnId: envelope.uuid,
-        startedAt: observedAt,
-        // A user echo lands on its own message identity, so this is the user row's key.
-        userItemId: agentJournalItemKey(identity)
-      }
+      currentTurn = opened
       publishLifecycle(currentTurn)
       deps.sink.setActivity?.(null)
     }
diff --git a/src/main/claude/claude-turn-lifecycle-item.ts b/src/main/claude/claude-turn-lifecycle-item.ts
index 00d7c4dd65e..ac679a5b47f 100644
--- a/src/main/claude/claude-turn-lifecycle-item.ts
+++ b/src/main/claude/claude-turn-lifecycle-item.ts
@@ -10,8 +10,9 @@ export type ClaudeCurrentTurn = {
   sessionId: string
   turnId: string
   startedAt: number
-  /** Provider key of the user echo that opened the turn. */
-  userItemId: string
+  /** Provider key of the user echo that opened the turn. Absent when the
+   *  provider resumed the work itself and there is no user row to anchor to. */
+  userItemId?: string
 }
 
 export type ClaudeTurnEnd = {
@@ -71,10 +72,15 @@ export function claudeTurnLifecycleItem(
             state: end.state,
             startedAt,
             completedAt: end.completedAt,
-            userItemId,
+            ...(userItemId === undefined ? {} : { userItemId }),
             ...(end.durationMs === undefined ? {} : { durationMs: end.durationMs })
           }
-        : { turnId, state: 'running', startedAt, userItemId }
+        : {
+            turnId,
+            state: 'running',
+            startedAt,
+            ...(userItemId === undefined ? {} : { userItemId })
+          }
     ),
     // The running row's ts is the turn start itself, so clients read no append lag.
     options: end ? {} : { observedAt: startedAt },
diff --git a/src/main/claude/claude-turn-opening.ts b/src/main/claude/claude-turn-opening.ts
new file mode 100644
index 00000000000..bafaa8edb4a
--- /dev/null
+++ b/src/main/claude/claude-turn-opening.ts
@@ -0,0 +1,48 @@
+// Which provider frame opens a Claude turn.
+//
+// Orca's own send echo used to be the only opener, while any `result` frame
+// closed the turn. That asymmetry is what leaves a working session reading
+// idle: the provider resumes on its own — a background task reports in and
+// wakes the agent after a `result` settled the turn — and nothing Orca sent
+// ever arrives to reopen one. The model's own output is the evidence that a
+// turn is running, the way Codex's `turn/start` is, so it opens one here.
+// Whichever opened it, the next `result` settles it.
+
+import {
+  claudeHasReplayContent,
+  type ClaudeMessageEnvelope
+} from './claude-structured-item-translation'
+import type { ClaudeCurrentTurn } from './claude-turn-lifecycle-item'
+
+export type ClaudeTurnOpeningInput = {
+  envelope: ClaudeMessageEnvelope
+  /** The raw frame: the turn boundary reads `parent_tool_use_id` off it, and an
+   *  absent field is not the same claim as an explicit `null`. */
+  frame: Record<string, unknown>
+  /** Orca dispatched this send and the provider is replaying it back. */
+  startsTurn: boolean
+  /** The frame appended journal content, so the provider produced just now. */
+  producedContent: boolean
+  hasOpenTurn: boolean
+  observedAt: number
+  /** Provider key of the user row, used only by the send echo. */
+  userItemId: string
+}
+
+export function claudeTurnOpenedByFrame(input: ClaudeTurnOpeningInput): ClaudeCurrentTurn | null {
+  // A subagent's frames are its parent turn's work, never a turn of their own.
+  if (input.frame.parent_tool_use_id !== null) {
+    return null
+  }
+  const { envelope, observedAt } = input
+  const turn = { sessionId: envelope.sessionId, turnId: envelope.uuid, startedAt: observedAt }
+  if (envelope.role === 'user') {
+    return input.startsTurn && claudeHasReplayContent(envelope)
+      ? { ...turn, userItemId: input.userItemId }
+      : null
+  }
+  // Resumed work has no user row to anchor to. Reopening only when no turn is
+  // open keeps every frame of one reply inside the turn its first frame opened,
+  // and keeps this off the path of a turn Orca is already tracking.
+  return !input.hasOpenTurn && input.producedContent ? turn : null
+}
diff --git a/src/main/claude/claude-turn-resumption.test.ts b/src/main/claude/claude-turn-resumption.test.ts
new file mode 100644
index 00000000000..5a94ac46cd9
--- /dev/null
+++ b/src/main/claude/claude-turn-resumption.test.ts
@@ -0,0 +1,179 @@
+// Regression for a structured Claude session that reported idle while it was
+// working. Reproduced from the journal of the reported session
+// (962e6f25…/epoch 3d214e6f…, 2026-09-13): a `result` settled the turn at
+// 13:56:06, a background task reported in at 13:58:59, and the agent then ran
+// tool calls until 14:05:18 — nine minutes in which the shared projector, and
+// so the sidebar row and the chat indicator, read `idle`.
+
+import { describe, expect, it, vi } from 'vitest'
+import type {
+  AgentJournalItemBody,
+  AgentJournalItemIdentity,
+  AgentJournalRenderItem
+} from '../../shared/agent-session-journal-types'
+import { agentJournalItemKey } from '../../shared/agent-session-journal-item-key'
+import { readAgentJournalTurn } from '../../shared/agent-session-turn-record'
+import {
+  hasUnansweredStructuredAgentSessionDispatch,
+  projectStructuredAgentSessionStatus
+} from '../../shared/structured-agent-session-projection'
+import type { StructuredAgentSessionEventSink } from '../native-chat/agent-session-wire/structured-agent-session-event-sink'
+import { createClaudeJournalTranslator } from './claude-structured-journal-translation'
+
+const SESSION = 'claude-session'
+
+function harness() {
+  const appended: { identity: AgentJournalItemIdentity; body: AgentJournalItemBody }[] = []
+  const sink: StructuredAgentSessionEventSink = {
+    appendItem: (identity, body) => appended.push({ identity, body }),
+    appendTombstone: () => {},
+    publish: vi.fn()
+  }
+  const translator = createClaudeJournalTranslator({ sink, fallbackIdPrefix: 'test' })
+  // The reducer keys items by identity and orders them by first append, so the
+  // render list the projector reads is the deduplicated append order.
+  const items = (): AgentJournalRenderItem[] => {
+    const byKey = new Map<string, AgentJournalRenderItem>()
+    appended.forEach(({ identity, body }, index) => {
+      const key = agentJournalItemKey(identity)
+      const existing = byKey.get(key)
+      byKey.set(key, {
+        itemId: key,
+        revision: (existing?.revision ?? 0) + 1,
+        body,
+        sequence: existing?.sequence ?? index,
+        observedAt: index
+      })
+    })
+    return [...byKey.values()].sort((a, b) => a.sequence - b.sequence)
+  }
+  return { translator, items }
+}
+
+function frame(
+  type: 'assistant' | 'user',
+  uuid: string,
+  content: unknown[],
+  parentToolUseId: string | null = null
+) {
+  return {
+    type: 'message' as const,
+    sessionId: 'orca-session',
+    ...(type === 'user' && parentToolUseId === null ? { startsTurn: true as const } : {}),
+    message: {
+      type,
+      uuid,
+      session_id: SESSION,
+      parent_tool_use_id: parentToolUseId,
+      message: { role: type, content }
+    }
+  }
+}
+
+/** The captured `task-notification` wake-up: a main-thread user frame Orca never
+ *  dispatched, so it carries no replay waiter and cannot start a turn. */
+function taskNotification(uuid: string) {
+  return {
+    type: 'message' as const,
+    sessionId: 'orca-session',
+    message: {
+      type: 'user',
+      uuid,
+      session_id: SESSION,
+      parent_tool_use_id: null,
+      message: {
+        role: 'user',
+        content: [{ type: 'text', text: '<task-notification><task-id>bfnmj08v6</task-id>' }]
+      }
+    }
+  }
+}
+
+function result(uuid: string) {
+  return {
+    type: 'message' as const,
+    sessionId: 'orca-session',
+    message: {
+      type: 'result',
+      subtype: 'success',
+      uuid,
+      session_id: SESSION,
+      duration_ms: 322_937
+    }
+  }
+}
+
+function projected(items: readonly AgentJournalRenderItem[]): string {
+  // No submission is outstanding: the send was acknowledged long ago, which is
+  // exactly the state in which the reported session fell back to idle.
+  expect(hasUnansweredStructuredAgentSessionDispatch([], null)).toBe(false)
+  return projectStructuredAgentSessionStatus(items, [], null)
+}
+
+describe('a Claude turn the provider resumed on its own', () => {
+  it('reports working while the agent runs tool calls after a result settled the turn', () => {
+    const { translator, items } = harness()
+
+    translator.handle(frame('user', 'u1', [{ type: 'text', text: 'go' }]))
+    expect(projected(items())).toBe('working')
+
+    translator.handle(result('r1'))
+    // The agent really did stop here, so idle is correct.
+    expect(projected(items())).toBe('idle')
+
+    // A background task reports in and wakes the agent; it starts working again.
+    translator.handle(taskNotification('n1'))
+    translator.handle(frame('assistant', 'a1', [{ type: 'text', text: 'Back on it.' }]))
+    expect(projected(items())).toBe('working')
+
+    translator.handle(
+      frame('assistant', 'a2', [
+        { type: 'tool_use', id: 'toolu_1', name: 'Bash', input: { command: 'rg foo' } }
+      ])
+    )
+    expect(projected(items())).toBe('working')
+
+    // The next result settles the turn the provider opened, so nothing over-claims.
+    translator.handle(result('r2'))
+    expect(projected(items())).toBe('idle')
+  })
+
+  it('gives the resumed turn its own record, with no user row to anchor to', () => {
+    const { translator, items } = harness()
+    translator.handle(frame('user', 'u1', [{ type: 'text', text: 'go' }]))
+    translator.handle(result('r1'))
+    translator.handle(frame('assistant', 'a1', [{ type: 'text', text: 'Back on it.' }]))
+
+    const turns = items().flatMap((item) => {
+      const turn = readAgentJournalTurn(item.body)
+      return turn ? [turn] : []
+    })
+    expect(turns.map((turn) => turn.state)).toEqual(['completed', 'running'])
+    expect(turns[1]?.turnId).toBe('a1')
+    expect(turns[1]?.userItemId).toBeUndefined()
+  })
+
+  it('leaves a settled turn settled when only a subagent is still producing', () => {
+    const { translator, items } = harness()
+    translator.handle(frame('user', 'u1', [{ type: 'text', text: 'go' }]))
+    translator.handle(result('r1'))
+
+    // Children outlive the turn that spawned them; their frames are not a turn.
+    translator.handle(
+      frame('assistant', 'a1', [{ type: 'text', text: 'child work' }], 'toolu_parent')
+    )
+    expect(projected(items())).toBe('idle')
+  })
+
+  it('does not reopen a turn that is already running', () => {
+    const { translator, items } = harness()
+    translator.handle(frame('user', 'u1', [{ type: 'text', text: 'go' }]))
+    translator.handle(frame('assistant', 'a1', [{ type: 'text', text: 'one' }]))
+    translator.handle(frame('assistant', 'a2', [{ type: 'text', text: 'two' }]))
+
+    const running = items().filter((item) => readAgentJournalTurn(item.body)?.state === 'running')
+    expect(running).toHaveLength(1)
+    expect(readAgentJournalTurn(running[0]!.body)?.turnId).toBe('u1')
+    expect(projected(items())).toBe('working')
+  })
+})