diff --git a/config/reliability-gates.jsonc b/config/reliability-gates.jsonc
index b64dbde80af..dafc1f8d251 100644
--- a/config/reliability-gates.jsonc
+++ b/config/reliability-gates.jsonc
@@ -100,9 +100,9 @@
         "https://github.com/stablyai/orca/blob/main/src/renderer/src/lib/agent-hibernation-coordinator.test.ts"
       ],
       "invariant": "Automatic hibernation must retain two stable confirmations and fresh execution-host evidence before shutdown. Skipping a workspace with no completed agent must not authorize a newly completed pane using stale client PTYs.",
-      "oracle": "100 remote workspaces containing working/waiting agents issue zero runtime calls. A skipped workspace completing while another inventory awaits remains ineligible until two later host-confirmed passes. Folder and git workspaces hibernate the exact host PTY; rejected/truncated inventories and intervening input/output or state changes block shutdown.",
+      "oracle": "100 remote workspaces containing working/waiting agents issue zero runtime calls. A skipped workspace completing while another inventory awaits remains ineligible until two later host-confirmed passes, and so does a workspace that only becomes runtime-owned while an inventory is outstanding — a pass carrying no host evidence for a workspace never counts as one of its two confirmations. Folder and git workspaces hibernate the exact host PTY; rejected/truncated inventories and intervening input/output or state changes block shutdown.",
       "commands": [
-        "ORCA_BACKGROUND_LAUNCH=1 pnpm test src/renderer/src/lib/agent-hibernation-coordinator.test.ts src/renderer/src/lib/agent-hibernation-planner.test.ts src/renderer/src/lib/agent-hibernation-confirmation.test.ts src/renderer/src/lib/agent-hibernation-pane-age.test.ts src/renderer/src/lib/agent-hibernation-output-activity.test.ts src/renderer/src/lib/agent-hibernation-visibility.test.ts src/renderer/src/lib/foreground-terminal-tabs.test.ts"
+        "ORCA_BACKGROUND_LAUNCH=1 pnpm test src/renderer/src/lib/agent-hibernation-coordinator.test.ts src/renderer/src/lib/agent-hibernation-planner.test.ts src/renderer/src/lib/agent-hibernation-confirmation.test.ts src/renderer/src/lib/agent-hibernation-pane-age.test.ts src/renderer/src/lib/agent-hibernation-output-activity.test.ts src/renderer/src/lib/agent-hibernation-visibility.test.ts src/renderer/src/lib/foreground-terminal-tabs.test.ts src/renderer/src/lib/agent-hibernation-runtime-liveness-race.test.ts"
       ],
       "testFiles": [
         "src/renderer/src/lib/agent-hibernation-coordinator.test.ts",
@@ -111,7 +111,8 @@
         "src/renderer/src/lib/agent-hibernation-pane-age.test.ts",
         "src/renderer/src/lib/agent-hibernation-output-activity.test.ts",
         "src/renderer/src/lib/agent-hibernation-visibility.test.ts",
-        "src/renderer/src/lib/foreground-terminal-tabs.test.ts"
+        "src/renderer/src/lib/foreground-terminal-tabs.test.ts",
+        "src/renderer/src/lib/agent-hibernation-runtime-liveness-race.test.ts"
       ],
       "assertionRefs": [
         {
@@ -123,6 +124,12 @@
             "fails closed on truncated runtime liveness samples",
             "fails closed when fresh runtime liveness rejects after an earlier good sample"
           ]
+        },
+        {
+          "file": "src/renderer/src/lib/agent-hibernation-runtime-liveness-race.test.ts",
+          "assertions": [
+            "requires host evidence when a workspace becomes runtime-owned during an inventory request"
+          ]
         }
       ],
       "evidenceRuns": [
@@ -130,10 +137,10 @@
           "date": "2026-09-07",
           "runner": "local",
           "platform": "macos",
-          "command": "ORCA_BACKGROUND_LAUNCH=1 pnpm test src/renderer/src/lib/agent-hibernation-coordinator.test.ts src/renderer/src/lib/agent-hibernation-planner.test.ts src/renderer/src/lib/agent-hibernation-confirmation.test.ts src/renderer/src/lib/agent-hibernation-pane-age.test.ts src/renderer/src/lib/agent-hibernation-output-activity.test.ts src/renderer/src/lib/agent-hibernation-visibility.test.ts src/renderer/src/lib/foreground-terminal-tabs.test.ts",
+          "command": "ORCA_BACKGROUND_LAUNCH=1 pnpm test src/renderer/src/lib/agent-hibernation-coordinator.test.ts src/renderer/src/lib/agent-hibernation-planner.test.ts src/renderer/src/lib/agent-hibernation-confirmation.test.ts src/renderer/src/lib/agent-hibernation-pane-age.test.ts src/renderer/src/lib/agent-hibernation-output-activity.test.ts src/renderer/src/lib/agent-hibernation-visibility.test.ts src/renderer/src/lib/foreground-terminal-tabs.test.ts src/renderer/src/lib/agent-hibernation-runtime-liveness-race.test.ts",
           "result": "passed",
-          "durationSeconds": 32.19,
-          "summary": "92 tests passed across seven coordinator, planner, confirmation, age, activity and visibility files."
+          "durationSeconds": 48.18,
+          "summary": "93 tests passed across eight coordinator, liveness-race, planner, confirmation, age, activity and visibility files."
         }
       ],
       "runtimeBudget": {
@@ -146,11 +153,11 @@
       },
       "redGreenEvidence": {
         "status": "complete",
-        "evidence": "Baseline made 101 runtime calls in the new no-completed-agent fixture; candidate makes zero. Existing confirmation, final recheck and failure-path assertions continue to pass, including completion during an outstanding request."
+        "evidence": "Baseline made 101 runtime calls in the new no-completed-agent fixture; candidate makes zero. Existing confirmation, final recheck and failure-path assertions continue to pass, including completion during an outstanding request. Separately, baseline hibernated a workspace that became runtime-owned mid-inventory one tick early, taking its first confirmation from a pass planned entirely from client PTYs; candidate withholds that pass and requires two host-confirmed ones."
       },
       "performanceBudget": {
         "required": true,
-        "evidence": "The 100-workspace fixture falls from 100 terminal.list calls plus one compatibility handshake to zero calls. Two-workspace confirmation/recheck fixture falls from five inventories to three. A single status scan and tab membership lookups precede existing requests. No new timer, concurrency, subprocess or retry; only active when experimental automatic hibernation is enabled."
+        "evidence": "The 100-workspace fixture falls from 100 terminal.list calls plus one compatibility handshake to zero calls. Two-workspace confirmation/recheck fixture falls from five inventories to three. A single status scan and tab membership lookups precede existing requests. Recomputing the required-worktree set from the post-await state adds one in-memory owner resolution per workspace per tick and no RPC. No new timer, concurrency, subprocess or retry; only active when experimental automatic hibernation is enabled."
       },
       "knownGaps": [
         "Remote contracts use mocked runtime replies; no live SSH/network-fault, Windows/Linux/WSL or relay run.",
diff --git a/src/renderer/src/lib/agent-hibernation-coordinator-test-fixture.ts b/src/renderer/src/lib/agent-hibernation-coordinator-test-fixture.ts
new file mode 100644
index 00000000000..985a2567469
--- /dev/null
+++ b/src/renderer/src/lib/agent-hibernation-coordinator-test-fixture.ts
@@ -0,0 +1,190 @@
+import { vi } from 'vitest'
+import type { AgentStatusEntry } from '../../../shared/agent-status-types'
+import type { TerminalLayoutSnapshot, TerminalTab } from '../../../shared/terminal-tab-types'
+import { useAppStore } from '@/store'
+import type { AppState } from '@/store/types'
+import { DEFAULT_AGENT_HIBERNATION_IDLE_MS } from './agent-hibernation-planner'
+import { resetAgentHibernationCoordinatorForTests } from './agent-hibernation-coordinator'
+import { hydrateDrivers } from './pane-manager/mobile-driver-state'
+import { resetForegroundTerminalTabIdsForTests } from './foreground-terminal-tabs'
+import { resetAgentHibernationOutputActivityForTests } from './agent-hibernation-output-activity'
+import {
+  observeHibernationPtyBindings,
+  resetHibernationPaneAgeForTests
+} from './agent-hibernation-pane-age'
+import { createCompatibleRuntimeStatusResponseIfNeeded } from '../runtime/runtime-compatibility-test-fixture'
+import { clearRuntimeCompatibilityCacheForTests } from '../runtime/runtime-rpc-client'
+
+export const NOW = 10_000_000
+export const LEAF = '11111111-1111-4111-8111-111111111111'
+
+export const mockRuntimeEnvironmentCall = vi.fn()
+
+vi.stubGlobal('window', {
+  api: {
+    runtimeEnvironments: {
+      call: mockRuntimeEnvironmentCall
+    }
+  }
+})
+
+export function tab(): TerminalTab {
+  return {
+    id: 'tab-1',
+    ptyId: null,
+    worktreeId: 'wt-bg',
+    title: 'Agent',
+    customTitle: null,
+    color: null,
+    sortOrder: 0,
+    createdAt: 1
+  }
+}
+
+export function layout(): TerminalLayoutSnapshot {
+  return {
+    root: { type: 'leaf', leafId: LEAF },
+    activeLeafId: LEAF,
+    expandedLeafId: null,
+    ptyIdsByLeafId: { [LEAF]: 'pty-1' }
+  }
+}
+
+export function entry(): AgentStatusEntry {
+  return {
+    state: 'done',
+    prompt: 'ship it',
+    updatedAt: NOW - DEFAULT_AGENT_HIBERNATION_IDLE_MS - 1,
+    stateStartedAt: NOW - DEFAULT_AGENT_HIBERNATION_IDLE_MS - 1,
+    paneKey: `tab-1:${LEAF}`,
+    tabId: 'tab-1',
+    worktreeId: 'wt-bg',
+    agentType: 'claude',
+    providerSession: { key: 'session_id', id: 'session-1' },
+    stateHistory: []
+  }
+}
+
+export function installEligibleState(
+  shutdownCompletedAgentPaneForHibernation = vi.fn(),
+  overrides: Partial<AppState> = {}
+): typeof shutdownCompletedAgentPaneForHibernation {
+  const e = entry()
+  const runtimeOwnerEnvironmentId = overrides.settings?.activeRuntimeEnvironmentId ?? undefined
+  useAppStore.setState({
+    settings: {
+      experimentalAgentHibernation: true,
+      agentHibernationIdleMs: DEFAULT_AGENT_HIBERNATION_IDLE_MS
+    } as never,
+    activeWorktreeId: 'wt-active',
+    repos: [],
+    worktreesByRepo: {
+      'fixture-repo': [
+        {
+          id: 'wt-bg',
+          repoId: 'fixture-repo',
+          hostId: 'local',
+          runtimeOwnerEnvironmentId
+        }
+      ]
+    } as never,
+    detectedWorktreesByRepo: {},
+    tabsByWorktree: { 'wt-bg': [tab()] },
+    terminalLayoutsByTabId: { 'tab-1': layout() },
+    ptyIdsByTabId: { 'tab-1': ['pty-1'] },
+    agentStatusByPaneKey: { [e.paneKey]: e },
+    sleepingAgentSessionsByPaneKey: {},
+    lastTerminalInputAtByPaneKey: {},
+    shutdownCompletedAgentPaneForHibernation: shutdownCompletedAgentPaneForHibernation as never,
+    shutdownWorktreeTerminals: vi.fn() as never,
+    ...overrides
+  })
+  // Why: a pane idle long enough to hibernate has necessarily been observed by earlier
+  // coordinator passes, so its PTY binding is old. Seed that here — otherwise the
+  // binding-age floor (which exists to stop a wake or app restart sleeping the whole
+  // backlog immediately) would defer every candidate on its first observed tick.
+  const state = useAppStore.getState()
+  observeHibernationPtyBindings({
+    tabsByWorktree: state.tabsByWorktree,
+    terminalLayoutsByTabId: state.terminalLayoutsByTabId,
+    now: NOW - DEFAULT_AGENT_HIBERNATION_IDLE_MS - 60_000,
+    idleMs: DEFAULT_AGENT_HIBERNATION_IDLE_MS
+  })
+  return shutdownCompletedAgentPaneForHibernation
+}
+
+export function runtimeListResult(ptyIds: string[], truncated = false) {
+  return {
+    terminals: ptyIds.map((ptyId) => ({
+      handle: `handle-${ptyId}`,
+      ptyId,
+      worktreeId: 'wt-bg',
+      worktreePath: '/tmp/wt-bg',
+      branch: 'feature',
+      tabId: `pty:${ptyId}`,
+      leafId: `pty:${ptyId}`,
+      title: 'Agent',
+      connected: true,
+      writable: true,
+      lastOutputAt: null,
+      preview: ''
+    })),
+    totalCount: ptyIds.length,
+    truncated
+  }
+}
+
+export function installRuntimeListResponses(
+  ...responses: (ReturnType<typeof runtimeListResult> | Error)[]
+): void {
+  const queue = [...responses]
+  mockRuntimeEnvironmentCall.mockImplementation((args: { method: string }) => {
+    const compatible = createCompatibleRuntimeStatusResponseIfNeeded(args)
+    if (compatible) {
+      return Promise.resolve(compatible)
+    }
+    if (args.method === 'terminal.list') {
+      const response = queue.shift() ?? runtimeListResult(['pty-1'])
+      if (response instanceof Error) {
+        return Promise.reject(response)
+      }
+      return Promise.resolve({
+        id: 'terminal-list',
+        ok: true,
+        result: response,
+        _meta: { runtimeId: 'runtime-1' }
+      })
+    }
+    return Promise.resolve({
+      id: 'default',
+      ok: true,
+      result: {},
+      _meta: { runtimeId: 'runtime-1' }
+    })
+  })
+}
+
+export function deferred<T>(): {
+  promise: Promise<T>
+  resolve: (value: T) => void
+  reject: (error: Error) => void
+} {
+  let resolve!: (value: T) => void
+  let reject!: (error: Error) => void
+  const promise = new Promise<T>((res, rej) => {
+    resolve = res
+    reject = rej
+  })
+  return { promise, resolve, reject }
+}
+
+export function resetAgentHibernationCoordinatorFixture(): void {
+  resetAgentHibernationCoordinatorForTests()
+  clearRuntimeCompatibilityCacheForTests()
+  resetForegroundTerminalTabIdsForTests()
+  resetAgentHibernationOutputActivityForTests()
+  resetHibernationPaneAgeForTests()
+  hydrateDrivers([])
+  mockRuntimeEnvironmentCall.mockReset()
+  vi.useRealTimers()
+}
diff --git a/src/renderer/src/lib/agent-hibernation-coordinator.test.ts b/src/renderer/src/lib/agent-hibernation-coordinator.test.ts
index bf6758c0d32..e73beb50d10 100644
--- a/src/renderer/src/lib/agent-hibernation-coordinator.test.ts
+++ b/src/renderer/src/lib/agent-hibernation-coordinator.test.ts
@@ -1,202 +1,33 @@
 import { tmpdir } from 'node:os'
 import { join } from 'node:path'
 import { afterEach, describe, expect, it, vi } from 'vitest'
-import type { AgentStatusEntry } from '../../../shared/agent-status-types'
-import type { TerminalLayoutSnapshot, TerminalTab } from '../../../shared/terminal-tab-types'
 import { useAppStore } from '@/store'
 import { DEFAULT_AGENT_HIBERNATION_IDLE_MS } from './agent-hibernation-planner'
 import {
-  resetAgentHibernationCoordinatorForTests,
   runAgentHibernationTick,
   startAgentHibernationCoordinator
 } from './agent-hibernation-coordinator'
-import { hydrateDrivers, setDriverForPty } from './pane-manager/mobile-driver-state'
-import {
-  registerVisibleTerminalTab,
-  resetForegroundTerminalTabIdsForTests,
-  setForegroundTerminalTabIds
-} from './foreground-terminal-tabs'
-import {
-  recordAgentHibernationPaneOutput,
-  resetAgentHibernationOutputActivityForTests
-} from './agent-hibernation-output-activity'
-import {
-  observeHibernationPtyBindings,
-  resetHibernationPaneAgeForTests
-} from './agent-hibernation-pane-age'
+import { setDriverForPty } from './pane-manager/mobile-driver-state'
+import { registerVisibleTerminalTab, setForegroundTerminalTabIds } from './foreground-terminal-tabs'
+import { recordAgentHibernationPaneOutput } from './agent-hibernation-output-activity'
 import { createCompatibleRuntimeStatusResponseIfNeeded } from '../runtime/runtime-compatibility-test-fixture'
-import { clearRuntimeCompatibilityCacheForTests } from '../runtime/runtime-rpc-client'
-import type { AppState } from '@/store/types'
+import {
+  deferred,
+  entry,
+  installEligibleState,
+  installRuntimeListResponses,
+  layout,
+  LEAF,
+  mockRuntimeEnvironmentCall,
+  NOW,
+  resetAgentHibernationCoordinatorFixture,
+  runtimeListResult,
+  tab
+} from './agent-hibernation-coordinator-test-fixture'
 
-const NOW = 10_000_000
-const LEAF = '11111111-1111-4111-8111-111111111111'
 const PI_TRANSCRIPT_PATH = join(tmpdir(), 'pi-session-1.jsonl')
 
-const mockRuntimeEnvironmentCall = vi.fn()
-
-vi.stubGlobal('window', {
-  api: {
-    runtimeEnvironments: {
-      call: mockRuntimeEnvironmentCall
-    }
-  }
-})
-
-function tab(): TerminalTab {
-  return {
-    id: 'tab-1',
-    ptyId: null,
-    worktreeId: 'wt-bg',
-    title: 'Agent',
-    customTitle: null,
-    color: null,
-    sortOrder: 0,
-    createdAt: 1
-  }
-}
-
-function layout(): TerminalLayoutSnapshot {
-  return {
-    root: { type: 'leaf', leafId: LEAF },
-    activeLeafId: LEAF,
-    expandedLeafId: null,
-    ptyIdsByLeafId: { [LEAF]: 'pty-1' }
-  }
-}
-
-function entry(): AgentStatusEntry {
-  return {
-    state: 'done',
-    prompt: 'ship it',
-    updatedAt: NOW - DEFAULT_AGENT_HIBERNATION_IDLE_MS - 1,
-    stateStartedAt: NOW - DEFAULT_AGENT_HIBERNATION_IDLE_MS - 1,
-    paneKey: `tab-1:${LEAF}`,
-    tabId: 'tab-1',
-    worktreeId: 'wt-bg',
-    agentType: 'claude',
-    providerSession: { key: 'session_id', id: 'session-1' },
-    stateHistory: []
-  }
-}
-
-function installEligibleState(
-  shutdownCompletedAgentPaneForHibernation = vi.fn(),
-  overrides: Partial<AppState> = {}
-): typeof shutdownCompletedAgentPaneForHibernation {
-  const e = entry()
-  const runtimeOwnerEnvironmentId = overrides.settings?.activeRuntimeEnvironmentId ?? undefined
-  useAppStore.setState({
-    settings: {
-      experimentalAgentHibernation: true,
-      agentHibernationIdleMs: DEFAULT_AGENT_HIBERNATION_IDLE_MS
-    } as never,
-    activeWorktreeId: 'wt-active',
-    repos: [],
-    worktreesByRepo: {
-      'fixture-repo': [
-        { id: 'wt-bg', repoId: 'fixture-repo', hostId: 'local', runtimeOwnerEnvironmentId }
-      ]
-    } as never,
-    detectedWorktreesByRepo: {},
-    tabsByWorktree: { 'wt-bg': [tab()] },
-    terminalLayoutsByTabId: { 'tab-1': layout() },
-    ptyIdsByTabId: { 'tab-1': ['pty-1'] },
-    agentStatusByPaneKey: { [e.paneKey]: e },
-    sleepingAgentSessionsByPaneKey: {},
-    lastTerminalInputAtByPaneKey: {},
-    shutdownCompletedAgentPaneForHibernation: shutdownCompletedAgentPaneForHibernation as never,
-    shutdownWorktreeTerminals: vi.fn() as never,
-    ...overrides
-  })
-  // Why: a pane idle long enough to hibernate has necessarily been observed by earlier
-  // coordinator passes, so its PTY binding is old. Seed that here — otherwise the
-  // binding-age floor (which exists to stop a wake or app restart sleeping the whole
-  // backlog immediately) would defer every candidate on its first observed tick.
-  const state = useAppStore.getState()
-  observeHibernationPtyBindings({
-    tabsByWorktree: state.tabsByWorktree,
-    terminalLayoutsByTabId: state.terminalLayoutsByTabId,
-    now: NOW - DEFAULT_AGENT_HIBERNATION_IDLE_MS - 60_000,
-    idleMs: DEFAULT_AGENT_HIBERNATION_IDLE_MS
-  })
-  return shutdownCompletedAgentPaneForHibernation
-}
-
-function runtimeListResult(ptyIds: string[], truncated = false) {
-  return {
-    terminals: ptyIds.map((ptyId) => ({
-      handle: `handle-${ptyId}`,
-      ptyId,
-      worktreeId: 'wt-bg',
-      worktreePath: '/tmp/wt-bg',
-      branch: 'feature',
-      tabId: `pty:${ptyId}`,
-      leafId: `pty:${ptyId}`,
-      title: 'Agent',
-      connected: true,
-      writable: true,
-      lastOutputAt: null,
-      preview: ''
-    })),
-    totalCount: ptyIds.length,
-    truncated
-  }
-}
-
-function installRuntimeListResponses(
-  ...responses: (ReturnType<typeof runtimeListResult> | Error)[]
-): void {
-  const queue = [...responses]
-  mockRuntimeEnvironmentCall.mockImplementation((args: { method: string }) => {
-    const compatible = createCompatibleRuntimeStatusResponseIfNeeded(args)
-    if (compatible) {
-      return Promise.resolve(compatible)
-    }
-    if (args.method === 'terminal.list') {
-      const response = queue.shift() ?? runtimeListResult(['pty-1'])
-      if (response instanceof Error) {
-        return Promise.reject(response)
-      }
-      return Promise.resolve({
-        id: 'terminal-list',
-        ok: true,
-        result: response,
-        _meta: { runtimeId: 'runtime-1' }
-      })
-    }
-    return Promise.resolve({
-      id: 'default',
-      ok: true,
-      result: {},
-      _meta: { runtimeId: 'runtime-1' }
-    })
-  })
-}
-
-function deferred<T>(): {
-  promise: Promise<T>
-  resolve: (value: T) => void
-  reject: (error: Error) => void
-} {
-  let resolve!: (value: T) => void
-  let reject!: (error: Error) => void
-  const promise = new Promise<T>((res, rej) => {
-    resolve = res
-    reject = rej
-  })
-  return { promise, resolve, reject }
-}
-
-afterEach(() => {
-  resetAgentHibernationCoordinatorForTests()
-  clearRuntimeCompatibilityCacheForTests()
-  resetForegroundTerminalTabIdsForTests()
-  resetAgentHibernationOutputActivityForTests()
-  resetHibernationPaneAgeForTests()
-  hydrateDrivers([])
-  mockRuntimeEnvironmentCall.mockReset()
-  vi.useRealTimers()
-})
+afterEach(resetAgentHibernationCoordinatorFixture)
 
 describe('agent sleep coordinator', () => {
   it('hibernates an eligible background worktree after two stable ticks', async () => {
diff --git a/src/renderer/src/lib/agent-hibernation-coordinator.ts b/src/renderer/src/lib/agent-hibernation-coordinator.ts
index 6497bd6fd77..c7287aed26c 100644
--- a/src/renderer/src/lib/agent-hibernation-coordinator.ts
+++ b/src/renderer/src/lib/agent-hibernation-coordinator.ts
@@ -80,7 +80,17 @@ function snapshotFromState(
     terminalLayoutsByTabId: state.terminalLayoutsByTabId,
     ptyIdsByTabId: state.ptyIdsByTabId,
     runtimeLivePtyIdsByWorktreeId: runtimeLiveness.runtimeLivePtyIdsByWorktreeId,
-    runtimeLivenessRequiredWorktreeIds: runtimeLiveness.runtimeLivenessRequiredWorktreeIds,
+    // Why: a workspace can gain tabs or resolve its runtime owner while the inventory above
+    // is in flight, and the plan is built from this later state. Union the fresh targets in
+    // so such a workspace is required-but-absent and the planner skips it, rather than
+    // answering for the execution host from client PTYs. Union, never replace: dropping a
+    // pre-await target would narrow the fail-closed set instead of widening it.
+    runtimeLivenessRequiredWorktreeIds: [
+      ...new Set([
+        ...runtimeLiveness.runtimeLivenessRequiredWorktreeIds,
+        ...getRuntimeLivenessTargetWorktrees(state, targetWorktreeId).keys()
+      ])
+    ],
     mobileLockedPtyIds: [...getAllDrivers()]
       .filter(([, driver]) => driver.kind === 'mobile')
       .map(([ptyId]) => ptyId),
diff --git a/src/renderer/src/lib/agent-hibernation-runtime-liveness-race.test.ts b/src/renderer/src/lib/agent-hibernation-runtime-liveness-race.test.ts
new file mode 100644
index 00000000000..6f338161a96
--- /dev/null
+++ b/src/renderer/src/lib/agent-hibernation-runtime-liveness-race.test.ts
@@ -0,0 +1,126 @@
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import { useAppStore } from '@/store'
+import { runAgentHibernationTick } from './agent-hibernation-coordinator'
+import { createCompatibleRuntimeStatusResponseIfNeeded } from '../runtime/runtime-compatibility-test-fixture'
+import {
+  deferred,
+  entry,
+  installEligibleState,
+  layout,
+  LEAF,
+  mockRuntimeEnvironmentCall,
+  resetAgentHibernationCoordinatorFixture,
+  runtimeListResult,
+  tab
+} from './agent-hibernation-coordinator-test-fixture'
+
+afterEach(resetAgentHibernationCoordinatorFixture)
+
+describe('agent sleep coordinator runtime-liveness races', () => {
+  it('requires host evidence when a workspace becomes runtime-owned during an inventory request', async () => {
+    const delayed = deferred<ReturnType<typeof runtimeListResult>>()
+    const lateTab = { ...tab(), id: 'tab-late', worktreeId: 'wt-late' }
+    const lateEntry = {
+      ...entry(),
+      tabId: 'tab-late',
+      worktreeId: 'wt-late',
+      paneKey: `tab-late:${LEAF}`
+    }
+    const lateList = {
+      ...runtimeListResult(['pty-late']),
+      terminals: runtimeListResult(['pty-late']).terminals.map((terminal) => ({
+        ...terminal,
+        worktreeId: 'wt-late'
+      }))
+    }
+    let firstListPending = true
+    mockRuntimeEnvironmentCall.mockImplementation(
+      (args: { method: string; params?: { worktree?: string } }) => {
+        const compatible = createCompatibleRuntimeStatusResponseIfNeeded(args)
+        if (compatible) {
+          return Promise.resolve(compatible)
+        }
+        if (args.method !== 'terminal.list') {
+          return Promise.resolve({ id: 'default', ok: true, result: {} })
+        }
+        const isLate = args.params?.worktree === 'id:wt-late'
+        if (!isLate && firstListPending) {
+          firstListPending = false
+          return delayed.promise.then((result) => ({
+            id: 'delayed',
+            ok: true,
+            result
+          }))
+        }
+        return Promise.resolve({
+          id: 'terminal-list',
+          ok: true,
+          result: isLate ? lateList : runtimeListResult(['pty-1'])
+        })
+      }
+    )
+    // Why: `wt-late` starts local-owned, so the pre-await target sample never lists it.
+    const shutdown = installEligibleState(vi.fn().mockResolvedValue(undefined), {
+      worktreesByRepo: {
+        'fixture-repo': [
+          {
+            id: 'wt-bg',
+            repoId: 'fixture-repo',
+            hostId: 'runtime:runtime-1',
+            runtimeOwnerEnvironmentId: 'runtime-1'
+          },
+          { id: 'wt-late', repoId: 'fixture-repo', hostId: 'local' }
+        ]
+      } as never,
+      tabsByWorktree: { 'wt-bg': [tab()], 'wt-late': [lateTab] },
+      terminalLayoutsByTabId: {
+        'tab-1': layout(),
+        'tab-late': {
+          root: { type: 'leaf', leafId: LEAF },
+          activeLeafId: LEAF,
+          expandedLeafId: null,
+          ptyIdsByLeafId: { [LEAF]: 'pty-late' }
+        }
+      },
+      ptyIdsByTabId: { 'tab-1': ['pty-1'], 'tab-late': ['pty-late'] },
+      agentStatusByPaneKey: {
+        [entry().paneKey]: entry(),
+        [lateEntry.paneKey]: lateEntry
+      }
+    })
+
+    const tick = runAgentHibernationTick()
+    await vi.waitFor(() =>
+      expect(mockRuntimeEnvironmentCall).toHaveBeenCalledWith(
+        expect.objectContaining({ method: 'terminal.list' })
+      )
+    )
+    // Runtime ownership resolves while the `wt-bg` inventory is still outstanding.
+    useAppStore.setState({
+      worktreesByRepo: {
+        'fixture-repo': ['wt-bg', 'wt-late'].map((id) => ({
+          id,
+          repoId: 'fixture-repo',
+          hostId: 'runtime:runtime-1',
+          runtimeOwnerEnvironmentId: 'runtime-1'
+        }))
+      } as never
+    })
+    delayed.resolve(runtimeListResult(['pty-1']))
+    await tick
+
+    // The racing pass has no host evidence for `wt-late`, so it must not count as one of
+    // the two confirmations; hibernating on the next tick would rest on client PTYs alone.
+    await runAgentHibernationTick()
+    expect(shutdown).not.toHaveBeenCalledWith('wt-late', expect.anything())
+
+    await runAgentHibernationTick()
+    expect(shutdown).toHaveBeenCalledWith(
+      'wt-late',
+      expect.objectContaining({
+        ptyId: 'pty-late',
+        expectedRuntimePtyId: 'pty-late'
+      })
+    )
+  })
+})