diff --git a/src/main/ipc/pty/provider/bind-listeners.ts b/src/main/ipc/pty/provider/bind-listeners.ts
index 3ba4cb9d1c0..0323d6995ea 100644
--- a/src/main/ipc/pty/provider/bind-listeners.ts
+++ b/src/main/ipc/pty/provider/bind-listeners.ts
@@ -12,11 +12,7 @@ import {
 import { localProvider } from './registry'
 import { clearProviderPtyState } from './state-cleanup'
 import { ORCA_LAYOUT_OWNER_IS_MAIN } from '../../../../shared/layout-owner-switch'
-import {
-  providerSnapshotRequiredPtys,
-  rendererVisibilityKnownPtys,
-  visibleRendererPtys
-} from '../delivery/visibility-state'
+import { providerSnapshotRequiredPtys, visibleRendererPtys } from '../delivery/visibility-state'
 import type { PtyIpcSession } from '../session'
 import { publishPtyEndpointLoss } from '../../../runtime/terminal/pty-endpoint-loss-signal'
 
@@ -31,10 +27,6 @@ export function bindProviderListeners(session: PtyIpcSession): void {
     localProvider.onWriteUnavailable?.((payload) => {
       // Before the window check: a headless host has no window, only remote streams.
       publishPtyEndpointLoss(payload.id)
-      // A pane remounts and re-attaches itself; main restores only streams no pane will.
-      if (!rendererVisibilityKnownPtys.has(payload.id)) {
-        session.runtime?.reattachPtyAfterEndpointLoss(payload.id)
-      }
       if (
         !session.mainWindow ||
         session.mainWindow.isDestroyed() ||
diff --git a/src/main/ipc/pty/pty-renderer-liveness-guard.test.ts b/src/main/ipc/pty/pty-renderer-liveness-guard.test.ts
index 256f70d5467..ac13f4754e8 100644
--- a/src/main/ipc/pty/pty-renderer-liveness-guard.test.ts
+++ b/src/main/ipc/pty/pty-renderer-liveness-guard.test.ts
@@ -3,7 +3,6 @@ import { setupPtyIpcSuite } from '../pty-ipc-test-harness'
 import { PtyWriteUnavailableError } from '../../providers/pty-write-unavailable-error'
 import { TERMINAL_INPUT_CHUNK_MAX_BYTES } from '../../../shared/terminal-input'
 import { registerPtyHandlers } from './register-handlers'
-import { rendererVisibilityKnownPtys } from './delivery/visibility-state'
 import { subscribeToPtyEndpointLoss } from '../../runtime/terminal/pty-endpoint-loss-signal'
 
 vi.mock('electron', () => import('../pty-ipc-mock-registry').then((m) => m.electronModuleMock()))
@@ -115,7 +114,7 @@ describe('pty:writeUnavailable renderer-liveness guard', () => {
   })
 
   describe('the daemon-death fan-out', () => {
-    function installProviderCapturingFanout(runtime?: unknown): (payload: { id: string }) => void {
+    function installProviderCapturingFanout(): (payload: { id: string }) => void {
       let fanout: ((payload: { id: string }) => void) | null = null
       installDaemonTestProvider({
         onWriteUnavailable: vi.fn((callback: (payload: { id: string }) => void) => {
@@ -123,7 +122,7 @@ describe('pty:writeUnavailable renderer-liveness guard', () => {
           return () => {}
         })
       })
-      registerPtyHandlers(mainWindow as never, runtime as never)
+      registerPtyHandlers(mainWindow as never)
       if (!fanout) {
         throw new Error('registerPtyHandlers did not subscribe to onWriteUnavailable')
       }
@@ -140,23 +139,6 @@ describe('pty:writeUnavailable renderer-liveness guard', () => {
       })
     })
 
-    it('re-attaches in main only the sessions no mounted pane will restore', () => {
-      const reattachPtyAfterEndpointLoss = vi.fn()
-      const fanout = installProviderCapturingFanout({
-        setPtyController: vi.fn(),
-        reattachPtyAfterEndpointLoss
-      })
-      rendererVisibilityKnownPtys.add('pane-1')
-      try {
-        fanout({ id: 'pane-1' })
-        fanout({ id: 'unmounted-1' })
-      } finally {
-        rendererVisibilityKnownPtys.delete('pane-1')
-      }
-
-      expect(reattachPtyAfterEndpointLoss.mock.calls).toEqual([['unmounted-1']])
-    })
-
     it('stays silent when the WebContents is destroyed under a live window', () => {
       const fanout = installProviderCapturingFanout()
       mainWindow.webContents.isDestroyed.mockReturnValue(true)
diff --git a/src/main/runtime/construction/runtime-construction-services.ts b/src/main/runtime/construction/runtime-construction-services.ts
index 2b84cd5718d..a278bd38b10 100644
--- a/src/main/runtime/construction/runtime-construction-services.ts
+++ b/src/main/runtime/construction/runtime-construction-services.ts
@@ -108,6 +108,7 @@ export abstract class RuntimeConstructionServices {
   protected abstract readCaughtUpRuledScreen(ptyId: string): RuledScreen | null
   protected abstract clearWaitBlockedStamp(ptyId: string): void
   protected abstract readRuledScreen(ptyId: string | null | undefined): RuledScreen | null
+  protected abstract readOutputClockAt(ptyId: string | null | undefined): number | null
   protected abstract headlessTerminals: Map<string, RuntimeHeadlessTerminal>
   protected abstract readHeadlessVisibleTerminalState(
     ptyId: string
diff --git a/src/main/runtime/construction/runtime-identity-state.ts b/src/main/runtime/construction/runtime-identity-state.ts
index f59357dffb2..46bc9cd6d1e 100644
--- a/src/main/runtime/construction/runtime-identity-state.ts
+++ b/src/main/runtime/construction/runtime-identity-state.ts
@@ -342,6 +342,7 @@ export abstract class OrcaRuntimeWithRuntimeId extends RuntimeConstructionServic
     getHookTurn: (ptyId, agent) => this.readTuiIdleHookTurnForPty(ptyId, agent),
     readScreenLines: (ptyId) => this.readLiveTerminalScreenLines(ptyId),
     readRuledScreen: (ptyId) => this.readRuledScreen(ptyId),
+    getOutputClockAt: (ptyId) => this.readOutputClockAt(ptyId),
     getTitleObservedAtEpochMs: (ptyId) =>
       (ptyId ? this.ptysById.get(ptyId)?.lastOscTitleEpochMs : null) ?? null
   }
diff --git a/src/main/runtime/terminal-subscriber-driven-daemon-attach.test.ts b/src/main/runtime/terminal-subscriber-driven-daemon-attach.test.ts
index a5aff180401..fa1067b1001 100644
--- a/src/main/runtime/terminal-subscriber-driven-daemon-attach.test.ts
+++ b/src/main/runtime/terminal-subscriber-driven-daemon-attach.test.ts
@@ -25,10 +25,7 @@ type RuntimeInternals = {
   ) => unknown
   issuePtyHandle: (pty: unknown) => string
   headlessTerminals: Map<string, unknown>
-  mainDaemonAttachments: {
-    hasPendingAttach: (ptyId: string) => boolean
-    inventoryWaiterIds: () => string[]
-  }
+  mainDaemonAttachments: { isUnreachable: (ptyId: string) => boolean }
   refreshPtyWorktreeRecordsWithControllerInventory: (
     worktrees: [],
     targetWorktreeId: string | null
@@ -410,7 +407,6 @@ describe('subscriber-driven daemon attach (never-activated tab)', () => {
     sendSubscribe(harness, 1, handle)
     await waitForSubscribed(harness, 1)
     await vi.waitFor(() => expect(model.attachCalls).toEqual([PTY_ID]))
-    expect(internals(runtime).mainDaemonAttachments.hasPendingAttach(PTY_ID)).toBe(true)
     expect(runtime.hasRemoteTerminalViewSubscriber(PTY_ID)).toBe(true)
     expect(model.emitData(PTY_ID, 'before inventory\r\n')).toBe(false)
 
@@ -418,13 +414,9 @@ describe('subscriber-driven daemon attach (never-activated tab)', () => {
     await internals(runtime).refreshPtyWorktreeRecordsWithControllerInventory([], null)
     await internals(runtime).refreshPtyWorktreeRecordsWithControllerInventory([], null)
     expect(model.attachCalls).toEqual([PTY_ID])
-    expect(internals(runtime).mainDaemonAttachments.inventoryWaiterIds()).toEqual([PTY_ID])
     refuseFirstAttach()
 
     await vi.waitFor(() => expect(model.attachCalls).toEqual([PTY_ID, PTY_ID]))
-    await vi.waitFor(() =>
-      expect(internals(runtime).mainDaemonAttachments.inventoryWaiterIds()).not.toContain(PTY_ID)
-    )
     expect(model.emitData(PTY_ID, 'after inventory\r\n')).toBe(true)
     await vi.waitFor(() => expect(outputText(harness)).toContain('after inventory'))
   })
@@ -440,44 +432,19 @@ describe('subscriber-driven daemon attach (never-activated tab)', () => {
     expect(read.tail.join('\n')).toContain('worker still printing')
   })
 
-  it('re-attaches a session main already holds after the daemon endpoint drops', async () => {
-    const { runtime, model } = setupNeverAttachedDaemonSession({ snapshotCapable: false })
-    await internals(runtime).refreshPtyWorktreeRecordsWithControllerInventory([], null)
-    await vi.waitFor(() => expect(model.attachCalls).toEqual([PTY_ID]))
-    expect(model.emitData(PTY_ID, 'before loss\r\n')).toBe(true)
-    model.sessions.get(PTY_ID)!.attached = false
-
-    runtime.reattachPtyAfterEndpointLoss(PTY_ID)
-
-    await vi.waitFor(() => expect(model.attachCalls).toEqual([PTY_ID, PTY_ID]))
-    expect(model.emitData(PTY_ID, 'after loss\r\n')).toBe(true)
-  })
-
-  it('fails a wait at once when main cannot attach the surviving session', async () => {
-    const { runtime, model, handle } = setupNeverAttachedDaemonSession({ snapshotCapable: false })
-    // The daemon refuses an attach-only request for a session it does not own.
-    model.sessions.delete(PTY_ID)
-
-    await expect(
-      runtime.waitForTerminal(handle, { condition: 'tui-idle', timeoutMs: 60_000 })
-    ).rejects.toThrow('terminal_not_connected_since_restart')
-    expect(model.attachCalls).toEqual([PTY_ID])
-  })
-
-  it('retries a refused attach when a wait arrives, instead of failing the wait', async () => {
+  it('fails a wait at once when main could not attach the surviving session', async () => {
     const { runtime, model, handle } = setupNeverAttachedDaemonSession({ snapshotCapable: false })
     const refuse = model.deferNextAttach(false)
     await internals(runtime).refreshPtyWorktreeRecordsWithControllerInventory([], null)
     refuse()
     await vi.waitFor(() =>
-      expect(internals(runtime).mainDaemonAttachments.hasPendingAttach(PTY_ID)).toBe(false)
+      expect(internals(runtime).mainDaemonAttachments.isUnreachable(PTY_ID)).toBe(true)
     )
 
     await expect(
-      runtime.waitForTerminal(handle, { condition: 'tui-idle', timeoutMs: 50 })
-    ).rejects.toThrow('timeout')
-    expect(model.attachCalls).toEqual([PTY_ID, PTY_ID])
-    expect(model.emitData(PTY_ID, 'attached on retry\r\n')).toBe(true)
+      runtime.waitForTerminal(handle, { condition: 'tui-idle', timeoutMs: 60_000 })
+    ).rejects.toThrow('terminal_not_connected_since_restart')
+    expect(model.attachCalls).toEqual([PTY_ID])
   })
 
   it('does not subscriber-attach or provider-read a session this app already spawned', async () => {
diff --git a/src/main/runtime/terminal/input/terminal-agent-prompt-render.ts b/src/main/runtime/terminal/input/terminal-agent-prompt-render.ts
index bb6a94d0097..d3d65985db9 100644
--- a/src/main/runtime/terminal/input/terminal-agent-prompt-render.ts
+++ b/src/main/runtime/terminal/input/terminal-agent-prompt-render.ts
@@ -138,21 +138,13 @@ export abstract class OrcaRuntimeWithCreateAgentPromptRenderGate extends OrcaRun
       launchReadiness?: boolean
     }
   ): Promise<RuntimeTerminalWait> {
-    const attaching = options?.condition === 'exit' ? null : this.attachTerminalOutputToMain(handle)
-    return attaching
-      ? attaching.then(() => this.waitForReachableTerminal(handle, options))
-      : this.waitForReachableTerminal(handle, options)
-  }
-
-  private waitForReachableTerminal(
-    handle: string,
-    options?: {
-      condition?: RuntimeTerminalWaitCondition
-      timeoutMs?: number
-      signal?: AbortSignal
-      launchReadiness?: boolean
+    if ((options?.condition ?? 'exit') !== 'exit') {
+      try {
+        this.assertTerminalOutputReachesMain(handle)
+      } catch (error) {
+        return Promise.reject(error)
+      }
     }
-  ): Promise<RuntimeTerminalWait> {
     // Switch point: a saved pane main holds with no terminal yet starts first (once, shared).
     const starting = ORCA_LAYOUT_OWNER_IS_MAIN
       ? this.startRestoredHandlePane(handle, options ?? {})
diff --git a/src/main/runtime/terminal/layout/terminal-view-presence.ts b/src/main/runtime/terminal/layout/terminal-view-presence.ts
index 49753cd6a84..685d0e93d1a 100644
--- a/src/main/runtime/terminal/layout/terminal-view-presence.ts
+++ b/src/main/runtime/terminal/layout/terminal-view-presence.ts
@@ -68,28 +68,18 @@ export abstract class OrcaRuntimeWithNotifyRemoteTerminalViewPresenceChanged ext
     return this.mainDaemonAttachments.isKnownUnattachedLocal(ptyId)
   }
 
-  /** Null when main already receives the terminal; else attaches it, rejecting if it cannot, since a wait could only time out. */
-  protected attachTerminalOutputToMain(handle: string): Promise<void> | null {
+  /** A survivor main holds no stream for can never satisfy a wait; say so instead of timing out. */
+  protected assertTerminalOutputReachesMain(handle: string): void {
     const ptyId = this.getLivePtyForHandle(handle)?.pty.ptyId
-    const attaching = ptyId ? this.mainDaemonAttachments.ensureAttached(ptyId) : null
-    return (
-      attaching?.then((attached) => {
-        if (!attached) {
-          throw new Error('terminal_not_connected_since_restart')
-        }
-      }) ?? null
-    )
+    if (ptyId && this.mainDaemonAttachments.isUnreachable(ptyId)) {
+      throw new Error('terminal_not_connected_since_restart')
+    }
   }
 
   protected reconcileMainDaemonAttach(ptyId: string): void {
     this.mainDaemonAttachments.reconcile(ptyId)
   }
 
-  /** The provider endpoint dropped this session's stream; restore main's attachment once it reconnects. */
-  reattachPtyAfterEndpointLoss(ptyId: string): void {
-    this.mainDaemonAttachments.reattachAfterEndpointLoss(ptyId)
-  }
-
   /** Mark a raw-output viewer without transferring terminal query authority. */
   registerRawTerminalViewSubscriber(ptyId: string): () => void {
     return this.terminalViewSubscribers.registerRaw(ptyId)
diff --git a/src/main/runtime/terminal/lifecycle/main-daemon-attachments.ts b/src/main/runtime/terminal/lifecycle/main-daemon-attachments.ts
index 116b3d7d4aa..aef131724d1 100644
--- a/src/main/runtime/terminal/lifecycle/main-daemon-attachments.ts
+++ b/src/main/runtime/terminal/lifecycle/main-daemon-attachments.ts
@@ -3,102 +3,70 @@ type MainDaemonAttachmentDependencies = {
   attachProvider: (ptyId: string) => Promise<boolean> | null
 }
 
-/** Who holds a session's stream: an attach in flight, a stream this run holds, or one an endpoint drop detached. */
-type StreamState =
-  | { kind: 'attaching'; restoring: boolean; attempt: Promise<boolean> }
-  | { kind: 'attached' }
-  | { kind: 'lost' }
-
 // Why capped: 100 concurrent snapshot attaches delayed the visible terminal's first echo by ~0.7 s.
 const MAX_CONCURRENT_ATTACHES = 4
 
 /** Main holds the stream for every live local daemon session it adopts, so its records fill without a mounted pane. */
 export class MainDaemonAttachments {
-  private readonly states = new Map<string, StreamState>()
-  private readonly inventoryWaiters = new Set<string>()
+  // Sessions whose stream this run already holds: spawned, pane-attached or main-attached.
+  private readonly attached = new Set<string>()
+  private readonly attaching = new Map<string, Promise<boolean>>()
   private readonly queued: (() => void)[] = []
   private running = 0
 
   constructor(private readonly deps: MainDaemonAttachmentDependencies) {}
 
-  /** This run's spawn or a pane's attach already carries the stream. */
   markSpawnPublished(ptyId: string): void {
-    this.states.set(ptyId, { kind: 'attached' })
+    this.attached.add(ptyId)
   }
 
-  /** Respawn or exit ends the generation whose stream this state described. */
+  /** Exit or respawn ends the generation whose stream this described. */
   forget(ptyId: string): void {
-    this.states.delete(ptyId)
-    this.inventoryWaiters.delete(ptyId)
+    this.attached.delete(ptyId)
+    this.attaching.delete(ptyId)
   }
 
   isKnownUnattachedLocal(ptyId: string): boolean {
-    return !this.states.has(ptyId) && this.deps.isUnattachedLocalCandidate(ptyId)
+    return !this.attached.has(ptyId) && this.deps.isUnattachedLocalCandidate(ptyId)
   }
 
-  hasPendingAttach(ptyId: string): boolean {
-    return this.states.get(ptyId)?.kind === 'attaching'
-  }
-
-  inventoryWaiterIds(): string[] {
-    return [...this.inventoryWaiters]
+  /** No stream and no attach in flight: nothing this session prints can reach main. */
+  isUnreachable(ptyId: string): boolean {
+    return !this.attaching.has(ptyId) && this.isKnownUnattachedLocal(ptyId)
   }
 
   /** Inventory proved the session live; attach it, or retry once an in-flight refusal settles. */
   reconcile(ptyId: string): void {
-    const state = this.states.get(ptyId)
-    if (state?.kind !== 'attaching') {
+    const attempt = this.attaching.get(ptyId)
+    if (!attempt) {
       this.ensure(ptyId)
       return
     }
-    if (this.inventoryWaiters.has(ptyId)) {
-      return
-    }
-    this.inventoryWaiters.add(ptyId)
-    void state.attempt.then(() => {
-      this.inventoryWaiters.delete(ptyId)
-      this.ensure(ptyId)
+    void attempt.then((attached) => {
+      if (!attached) {
+        this.ensure(ptyId)
+      }
     })
   }
 
-  /** An endpoint drop detached a stream no pane will restore; re-attach it once the daemon answers. */
-  reattachAfterEndpointLoss(ptyId: string): void {
-    this.states.set(ptyId, { kind: 'lost' })
-    this.ensure(ptyId)
-  }
-
   ensure(ptyId: string): void {
-    void this.ensureAttached(ptyId)
-  }
-
-  /** Null when the stream needs nothing from main; otherwise whether an attach (or retry) got it. */
-  ensureAttached(ptyId: string): Promise<boolean> | null {
-    const state = this.states.get(ptyId)
-    if (state?.kind === 'attaching') {
-      return state.attempt
+    if (this.attaching.has(ptyId) || !this.isKnownUnattachedLocal(ptyId)) {
+      return
     }
-    const restoring = state?.kind === 'lost'
-    if (state?.kind === 'attached' || (!restoring && !this.isKnownUnattachedLocal(ptyId))) {
-      return null
-    }
-    const attaching: StreamState = { kind: 'attaching', restoring, attempt: Promise.resolve(false) }
-    this.states.set(ptyId, attaching)
-    attaching.attempt = this.attach(ptyId, attaching).then((attached) => {
-      if (this.states.get(ptyId) === attaching) {
-        if (attached) {
-          this.states.set(ptyId, { kind: 'attached' })
-        } else if (restoring) {
-          this.states.set(ptyId, { kind: 'lost' })
-        } else {
-          this.states.delete(ptyId)
-        }
+    const attempt = this.attach(ptyId)
+    this.attaching.set(ptyId, attempt)
+    void attempt.then((attached) => {
+      if (this.attaching.get(ptyId) !== attempt) {
+        return
+      }
+      this.attaching.delete(ptyId)
+      if (attached) {
+        this.attached.add(ptyId)
       }
-      return attached
     })
-    return attaching.attempt
   }
 
-  private async attach(ptyId: string, attaching: StreamState): Promise<boolean> {
+  private async attach(ptyId: string): Promise<boolean> {
     if (this.running >= MAX_CONCURRENT_ATTACHES) {
       // The finishing attach hands its slot over without releasing it.
       await new Promise<void>((resolve) => this.queued.push(resolve))
@@ -106,9 +74,9 @@ export class MainDaemonAttachments {
       this.running += 1
     }
     try {
-      // A pane's attach or a respawn replaced this state while it waited.
-      if (this.states.get(ptyId) !== attaching) {
-        return this.states.get(ptyId)?.kind === 'attached'
+      // A pane may have attached, or the session exited, while this waited.
+      if (this.attached.has(ptyId) || !this.deps.isUnattachedLocalCandidate(ptyId)) {
+        return false
       }
       return (await this.deps.attachProvider(ptyId)) ?? false
     } catch {
diff --git a/src/main/runtime/terminal/lifecycle/terminal-view-resources.ts b/src/main/runtime/terminal/lifecycle/terminal-view-resources.ts
index d65e42647d7..7e37e8b0259 100644
--- a/src/main/runtime/terminal/lifecycle/terminal-view-resources.ts
+++ b/src/main/runtime/terminal/lifecycle/terminal-view-resources.ts
@@ -160,10 +160,7 @@ export abstract class OrcaRuntimeWithFitOverrideListeners extends OrcaRuntimeWit
       const pty = this.ptysById.get(ptyId)
       return pty !== undefined && pty.connectionId === null && pty.connected
     },
-    attachProvider: (ptyId) => {
-      const attach = this.ptyController?.attach
-      return attach ? (async () => attach(ptyId))() : null
-    }
+    attachProvider: (ptyId) => this.ptyController?.attach?.(ptyId) ?? null
   })
 
   // Remote xterms own query replies; ref-count streams and retain suppression through mobile soft-leave grace (terminal-query-authority.md).
diff --git a/src/main/runtime/terminal/output/terminal-buffer-operations.ts b/src/main/runtime/terminal/output/terminal-buffer-operations.ts
index bc6ed49cc16..318de8da6c7 100644
--- a/src/main/runtime/terminal/output/terminal-buffer-operations.ts
+++ b/src/main/runtime/terminal/output/terminal-buffer-operations.ts
@@ -229,10 +229,15 @@ export abstract class OrcaRuntimeWithSerializeMainTerminalBuffer extends OrcaRun
   startReattachedOutputClock(ptyId: string): void {
     const pty = this.ptysById.get(ptyId)
     if (pty && pty.lastOutputAt === null) {
-      pty.outputObservedSince ??= Date.now()
+      pty.outputObservedSince = Date.now()
     }
   }
 
+  protected readOutputClockAt(ptyId: string | null | undefined): number | null {
+    const pty = ptyId ? this.ptysById.get(ptyId) : undefined
+    return pty ? (pty.lastOutputAt ?? pty.outputObservedSince ?? null) : null
+  }
+
   // Restore RPC bytes bypass onPtyData; seed read/list state without waiters, orchestration events or fresh-output clocks.
   seedTerminalRestoreTail(ptyId: string, restore: { text?: string; lastTitle?: string }): void {
     const seed = restore.text ? buildRestoredTerminalTailSeed(restore.text) : null
diff --git a/src/main/runtime/terminal/wait/terminal-idle-polls.ts b/src/main/runtime/terminal/wait/terminal-idle-polls.ts
index 2498defe2bb..8ee828d733a 100644
--- a/src/main/runtime/terminal/wait/terminal-idle-polls.ts
+++ b/src/main/runtime/terminal/wait/terminal-idle-polls.ts
@@ -13,12 +13,12 @@ import {
 import { buildTerminalWaitText } from '../../terminal-wait-tail-state'
 import {
   evaluateTuiIdle,
-  outputClockAt,
   type QuietForegroundLane,
   type TuiIdleVerdict
 } from '../../tui-idle-evidence'
 import {
   leafTuiIdleEvidence,
+  outputClockOf,
   ptyTuiIdleEvidence,
   type TuiIdleEvidenceSource
 } from '../../tui-idle-evidence-source'
@@ -146,7 +146,7 @@ export class RuntimeTerminalIdlePolls {
         ready: () => buildPtyTerminalWaitResult(handle, 'tui-idle', pty),
         blocked: (reason) => buildPtyTerminalWaitBlockedResult(handle, 'tui-idle', pty, reason),
         isQuiet: (lane) =>
-          isQuietForQuiescence(outputClockAt(pty), this.deps.quiescenceMs, lane, () =>
+          isQuietForQuiescence(outputClockOf(this.deps, pty), this.deps.quiescenceMs, lane, () =>
             this.deps.hasCommandPainted(pty.ptyId)
           )
       }
@@ -166,7 +166,7 @@ export class RuntimeTerminalIdlePolls {
       blocked: (reason) => buildTerminalWaitBlockedResult(handle, 'tui-idle', live(), reason),
       isQuiet: (lane) =>
         isQuietForQuiescence(
-          live().lastOutputAt,
+          outputClockOf(this.deps, live()),
           this.deps.quiescenceMs,
           lane,
           () => !leaf.ptyId || this.deps.hasCommandPainted(leaf.ptyId)
diff --git a/src/main/runtime/tui-idle-evidence-source.ts b/src/main/runtime/tui-idle-evidence-source.ts
index 9eea2e5a0f4..a03accb6327 100644
--- a/src/main/runtime/tui-idle-evidence-source.ts
+++ b/src/main/runtime/tui-idle-evidence-source.ts
@@ -14,11 +14,10 @@ import {
   type AgentStateVerdict
 } from './agent-state-rules/agent-state-rules-engine'
 import type { TuiIdleHookTurn } from './tui-idle-hook-lane'
-import {
-  outputClockAt,
-  type FirstPartyAgentStatus,
-  type TuiIdleEvaluationInput,
-  type TuiIdleEvidenceRecord
+import type {
+  FirstPartyAgentStatus,
+  TuiIdleEvaluationInput,
+  TuiIdleEvidenceRecord
 } from './tui-idle-evidence'
 
 /** The runtime state every tui-idle site reads its evidence from. */
@@ -36,6 +35,27 @@ export type TuiIdleEvidenceSource = {
   readRuledScreen?(ptyId: string | null | undefined): RuledScreen | null
   /** When the PTY last observed a title of its own. Absent, no title has an age. */
   getTitleObservedAtEpochMs?(ptyId: string | null | undefined): number | null
+  /** The PTY's quiet clock: its last output, else when main began receiving its silent stream. */
+  getOutputClockAt?(ptyId: string | null | undefined): number | null
+}
+
+/** One clock per terminal, read by ptyId, so a pane leaf and its PTY settle alike. */
+export function outputClockOf(
+  source: Pick<TuiIdleEvidenceSource, 'getOutputClockAt'>,
+  record: { ptyId: string | null; lastOutputAt: number | null }
+): number | null {
+  return source.getOutputClockAt?.(record.ptyId) ?? record.lastOutputAt
+}
+
+function evidenceRecord(
+  source: TuiIdleEvidenceSource,
+  record: TuiIdleEvidenceRecord & { ptyId: string | null }
+): TuiIdleEvidenceRecord {
+  return {
+    lastAgentStatus: record.lastAgentStatus,
+    lastOscTitle: record.lastOscTitle,
+    lastOutputAt: outputClockOf(source, record)
+  }
 }
 
 // Why per agent: every other agent keeps the live screen its rules were recorded against.
@@ -62,7 +82,7 @@ function readAgentRuleVerdict(
     readScreenLines,
     readText: () => waitText().toLowerCase(),
     readTitleStatus: () => record.lastAgentStatus,
-    hasOutputClock: outputClockAt(record) !== null
+    hasOutputClock: record.lastOutputAt !== null
   })
 }
 
@@ -106,14 +126,15 @@ export function leafTuiIdleEvidence(
   const waitText = lazyWaitText(readWaitText)
   const agent = source.getPaneAgent(leaf.ptyId)
   const readScreen = screenReader(source, agent, leaf.ptyId)
+  const record = evidenceRecord(source, leaf)
   return {
-    record: leaf,
+    record,
     readTailBlockedReason: () => detectTerminalWaitBlockedReason(waitText()),
     rendererTitle: leaf.paneTitle ?? source.getTabTitle(leaf.tabId),
     readPositiveBodyEvidence: () =>
-      isKnownReadyPromptBody(waitText(), agent, readScreen, leaf.lastOutputAt !== null),
+      isKnownReadyPromptBody(waitText(), agent, readScreen, record.lastOutputAt !== null),
     readQuietReadyBodyEvidence: () => isQuietReadyScreenBody(waitText(), agent, readScreen),
-    readAgentRuleVerdict: () => readAgentRuleVerdict(agent, leaf, readScreen, waitText),
+    readAgentRuleVerdict: () => readAgentRuleVerdict(agent, record, readScreen, waitText),
     readScreenInputVeto: screenInputVetoReader(source, agent, leaf.ptyId),
     titleObservedAtEpochMs: source.getTitleObservedAtEpochMs?.(leaf.ptyId) ?? null,
     agent,
@@ -131,17 +152,18 @@ export function ptyTuiIdleEvidence(
   const waitText = lazyWaitText(readWaitText)
   const agent = source.getPaneAgent(pty.ptyId)
   const readScreen = screenReader(source, agent, pty.ptyId)
+  const record = evidenceRecord(source, pty)
   return {
-    record: pty,
+    record,
     readTailBlockedReason: () => detectTerminalWaitBlockedReason(waitText()),
     readPositiveBodyEvidence: () =>
       (agent !== 'qoder' &&
         agent !== 'qoder-cn' &&
         agent !== 'hermes' &&
         source.getAdoptedPtyIdleStatus(pty) === 'idle') ||
-      isKnownReadyPromptBody(waitText(), agent, readScreen, outputClockAt(pty) !== null),
+      isKnownReadyPromptBody(waitText(), agent, readScreen, record.lastOutputAt !== null),
     readQuietReadyBodyEvidence: () => isQuietReadyScreenBody(waitText(), agent, readScreen),
-    readAgentRuleVerdict: () => readAgentRuleVerdict(agent, pty, readScreen, waitText),
+    readAgentRuleVerdict: () => readAgentRuleVerdict(agent, record, readScreen, waitText),
     readScreenInputVeto: screenInputVetoReader(source, agent, pty.ptyId),
     titleObservedAtEpochMs: pty.lastOscTitleEpochMs,
     agent,
diff --git a/src/main/runtime/tui-idle-evidence.ts b/src/main/runtime/tui-idle-evidence.ts
index d9423b4108f..98b57276e3f 100644
--- a/src/main/runtime/tui-idle-evidence.ts
+++ b/src/main/runtime/tui-idle-evidence.ts
@@ -27,15 +27,9 @@ import { evaluateHookTurn, type TuiIdleHookTurn } from './tui-idle-hook-lane'
 export type TuiIdleEvidenceRecord = {
   lastAgentStatus: AgentStatus | null
   lastOutputAt: number | null
-  outputObservedSince?: number | null
   lastOscTitle?: string | null
 }
 
-/** The output clock: last output, or when main began receiving a stream that has stayed silent since. */
-export function outputClockAt(record: TuiIdleEvidenceRecord): number | null {
-  return record.lastOutputAt ?? record.outputObservedSince ?? null
-}
-
 export type FirstPartyAgentStatus = {
   state: AgentStatusState
   updatedAt: number
@@ -109,8 +103,7 @@ export function hasSustainedTitleIdle(
 
 /** Why a missing clock is not quiet: an adopted or restored pane cannot measure it. */
 function hasQuietOutput(record: TuiIdleEvidenceRecord, quiescenceMs: number): boolean {
-  const clock = outputClockAt(record)
-  return clock !== null && Date.now() - clock >= quiescenceMs
+  return record.lastOutputAt !== null && Date.now() - record.lastOutputAt >= quiescenceMs
 }
 
 /** Closed lanes require stronger rest evidence; after-paint lanes require agent output beyond shell echo; open unknown panes may settle without an output clock. */
diff --git a/src/main/runtime/tui-idle-output-clock.test.ts b/src/main/runtime/tui-idle-output-clock.test.ts
index a0c2176b898..ccfe254faaf 100644
--- a/src/main/runtime/tui-idle-output-clock.test.ts
+++ b/src/main/runtime/tui-idle-output-clock.test.ts
@@ -1,18 +1,37 @@
-import { afterEach, describe, expect, it, vi } from 'vitest'
-import { hasQuietReadyScreen } from './tui-idle-evidence'
+import './rpc/unused-default-rpc-methods.test-fixture'
+import { afterEach, expect, it, vi } from 'vitest'
+import { runtimeWithLeaf } from './orca-runtime-pty-leaf.test-fixture'
+import { evaluateTuiIdle } from './tui-idle-evidence'
+import { leafTuiIdleEvidence, ptyTuiIdleEvidence } from './tui-idle-evidence-source'
 
-const QUIESCENCE_MS = 3000
+const PTY_ID = 'repo-1::/tmp/wt@@1a2b3c4d'
+const CODEX_COMPOSER = '› Ask Codex to do anything'
 
 afterEach(() => {
   vi.useRealTimers()
 })
 
-describe('output clock for a stream main attached after the process last printed', () => {
-  it('measures quiet from when main began receiving a stream that has printed nothing since', () => {
-    vi.useFakeTimers({ now: 100_000 })
-    const silent = { lastAgentStatus: null, lastOutputAt: null, outputObservedSince: 100_000 }
-    expect(hasQuietReadyScreen(silent, 'codex', () => true, QUIESCENCE_MS)).toBe(false)
-    vi.advanceTimersByTime(QUIESCENCE_MS)
-    expect(hasQuietReadyScreen(silent, 'codex', () => true, QUIESCENCE_MS)).toBe(true)
-  })
+it('a silent reattached Codex reads quiet on its PTY and its pane leaf alike', () => {
+  vi.useFakeTimers({ now: 100_000 })
+  const { runtime, leaf } = runtimeWithLeaf(PTY_ID)
+  runtime.seedTerminalRestoreTail(PTY_ID, { text: CODEX_COMPOSER })
+  runtime.startReattachedOutputClock(PTY_ID)
+  const pty = runtime['ptysById'].get(PTY_ID)!
+  const source = {
+    ...runtime['tuiIdleEvidenceSource'],
+    getPaneAgent: () => 'codex' as const,
+    readScreenLines: () => [CODEX_COMPOSER],
+    readRuledScreen: () => ({ lines: [CODEX_COMPOSER], alternateScreen: false })
+  }
+  const verdicts = () =>
+    [
+      evaluateTuiIdle(ptyTuiIdleEvidence(source, pty, () => pty.preview)),
+      evaluateTuiIdle(leafTuiIdleEvidence(source, leaf, () => leaf.preview))
+    ].map((verdict) => verdict.kind)
+
+  expect(verdicts()).toEqual(['pending', 'pending'])
+  vi.advanceTimersByTime(source.quiescenceMs)
+  // Neither record ever saw output; the clock is main's observation since the reattach.
+  expect([pty.lastOutputAt, leaf.lastOutputAt]).toEqual([null, null])
+  expect(verdicts()).toEqual(['ready-strong', 'ready-strong'])
 })
diff --git a/src/main/runtime/workspaces/workspace-activation.ts b/src/main/runtime/workspaces/workspace-activation.ts
index 9e38a24b287..c1bb414ebb0 100644
--- a/src/main/runtime/workspaces/workspace-activation.ts
+++ b/src/main/runtime/workspaces/workspace-activation.ts
@@ -221,7 +221,7 @@ export abstract class OrcaRuntimeWithActivateManagedWorktree extends OrcaRuntime
       signal
     }: { requireComposerMarker?: boolean; stopOnDialog?: boolean; signal?: AbortSignal } = {}
   ): Promise<RuntimeTerminalWait> {
-    await this.attachTerminalOutputToMain(handle)
+    this.assertTerminalOutputReachesMain(handle)
     const initialPtyId =
       this.getLivePtyForHandle(handle)?.pty.ptyId ?? this.getLiveLeafForHandle(handle).leaf.ptyId
     const stop = new AbortController()