diff --git a/src/renderer/src/components/terminal-pane/TerminalPane.tsx b/src/renderer/src/components/terminal-pane/TerminalPane.tsx
index d49b48c0fa7..bda9d525d18 100644
--- a/src/renderer/src/components/terminal-pane/TerminalPane.tsx
+++ b/src/renderer/src/components/terminal-pane/TerminalPane.tsx
@@ -111,6 +111,7 @@ import { keybindingMatchesAction } from '../../../../shared/keybindings'
 import { pasteTerminalClipboard } from './terminal-clipboard-paste'
 import { scheduleImagePasteWebglAtlasRecovery } from './terminal-webgl-paste-recovery'
 import { restoreTerminalFitToDesktop, restoreTerminalFitsToDesktop } from './terminal-fit-restore'
+import { useVisibleTerminalWorktreeClaim } from './use-visible-terminal-worktree-claim'
 
 // Why: registry lives in a leaf module so the store slice can import it
 // without re-entering the `slice → TerminalPane → store → slice` cycle
@@ -261,6 +262,8 @@ export default function TerminalPane({
   const isVisibleRef = useRef(isVisible)
   isVisibleRef.current = isVisible
 
+  useVisibleTerminalWorktreeClaim({ isVisible, worktreeId })
+
   const [expandedPaneId, setExpandedPaneId] = useState<number | null>(null)
   // Why: tracked in React state (not derived from managerRef.getPanes().length)
   // so the render containing the portal map (which reads the imperative pane
diff --git a/src/renderer/src/components/terminal-pane/use-visible-terminal-worktree-claim.test.ts b/src/renderer/src/components/terminal-pane/use-visible-terminal-worktree-claim.test.ts
new file mode 100644
index 00000000000..79c17b4fcca
--- /dev/null
+++ b/src/renderer/src/components/terminal-pane/use-visible-terminal-worktree-claim.test.ts
@@ -0,0 +1,54 @@
+import type * as ReactModule from 'react'
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import {
+  getForegroundTerminalWorktreeIds,
+  resetForegroundTerminalWorktreeIdsForTests
+} from '@/lib/foreground-terminal-worktrees'
+import { useVisibleTerminalWorktreeClaim } from './use-visible-terminal-worktree-claim'
+
+const reactEffects = vi.hoisted(() => ({
+  layoutEffects: [] as (() => void | (() => void))[],
+  passiveEffects: [] as (() => void | (() => void))[]
+}))
+
+vi.mock('react', async (importOriginal) => {
+  const actual = await importOriginal<typeof ReactModule>()
+  return {
+    ...actual,
+    useEffect: (effect: () => void | (() => void)) => {
+      reactEffects.passiveEffects.push(effect)
+    },
+    useLayoutEffect: (effect: () => void | (() => void)) => {
+      reactEffects.layoutEffects.push(effect)
+    }
+  }
+})
+
+afterEach(() => {
+  resetForegroundTerminalWorktreeIdsForTests()
+  reactEffects.layoutEffects = []
+  reactEffects.passiveEffects = []
+})
+
+describe('useVisibleTerminalWorktreeClaim', () => {
+  it('registers visible panes through a layout effect', () => {
+    useVisibleTerminalWorktreeClaim({ isVisible: true, worktreeId: 'wt-visible' })
+
+    expect(reactEffects.passiveEffects).toHaveLength(0)
+    expect(reactEffects.layoutEffects).toHaveLength(1)
+
+    const cleanup = reactEffects.layoutEffects[0]()
+    expect(getForegroundTerminalWorktreeIds()).toEqual(['wt-visible'])
+
+    cleanup?.()
+    expect(getForegroundTerminalWorktreeIds()).toEqual([])
+  })
+
+  it('does not claim hidden panes', () => {
+    useVisibleTerminalWorktreeClaim({ isVisible: false, worktreeId: 'wt-hidden' })
+
+    reactEffects.layoutEffects[0]()
+
+    expect(getForegroundTerminalWorktreeIds()).toEqual([])
+  })
+})
diff --git a/src/renderer/src/components/terminal-pane/use-visible-terminal-worktree-claim.ts b/src/renderer/src/components/terminal-pane/use-visible-terminal-worktree-claim.ts
new file mode 100644
index 00000000000..9cb69bf84af
--- /dev/null
+++ b/src/renderer/src/components/terminal-pane/use-visible-terminal-worktree-claim.ts
@@ -0,0 +1,21 @@
+import { useLayoutEffect } from 'react'
+import { registerVisibleTerminalWorktree } from '@/lib/foreground-terminal-worktrees'
+
+type VisibleTerminalWorktreeClaimOptions = {
+  isVisible: boolean
+  worktreeId: string
+}
+
+export function useVisibleTerminalWorktreeClaim({
+  isVisible,
+  worktreeId
+}: VisibleTerminalWorktreeClaimOptions): void {
+  useLayoutEffect(() => {
+    if (!isVisible) {
+      return
+    }
+    // Why: agent sleep must fail closed before paint for any pane the user can
+    // see, even when global active-worktree state is between views.
+    return registerVisibleTerminalWorktree(worktreeId)
+  }, [isVisible, worktreeId])
+}
diff --git a/src/renderer/src/lib/agent-hibernation-coordinator.test.ts b/src/renderer/src/lib/agent-hibernation-coordinator.test.ts
index 811b8ed48a4..f6e4f8f2a37 100644
--- a/src/renderer/src/lib/agent-hibernation-coordinator.test.ts
+++ b/src/renderer/src/lib/agent-hibernation-coordinator.test.ts
@@ -9,6 +9,7 @@ import {
 } from './agent-hibernation-coordinator'
 import { hydrateDrivers, setDriverForPty } from './pane-manager/mobile-driver-state'
 import {
+  registerVisibleTerminalWorktree,
   resetForegroundTerminalWorktreeIdsForTests,
   setForegroundTerminalWorktreeIds
 } from './foreground-terminal-worktrees'
@@ -239,6 +240,27 @@ describe('agent sleep coordinator', () => {
     expect(shutdown).not.toHaveBeenCalled()
   })
 
+  it('does not hibernate a worktree with a visible mounted terminal pane', async () => {
+    vi.useFakeTimers()
+    const shutdown = installEligibleState(vi.fn().mockResolvedValue(undefined))
+    const unregister = registerVisibleTerminalWorktree('wt-bg')
+    startAgentHibernationCoordinator({ intervalMs: 1000, now: () => NOW })
+
+    await vi.advanceTimersByTimeAsync(3000)
+    expect(shutdown).not.toHaveBeenCalled()
+
+    unregister()
+    await vi.advanceTimersByTimeAsync(1000)
+    await vi.advanceTimersByTimeAsync(1000)
+
+    expect(shutdown).toHaveBeenCalledWith('wt-bg', {
+      paneKey: `tab-1:${LEAF}`,
+      tabId: 'tab-1',
+      leafId: LEAF,
+      ptyId: 'pty-1'
+    })
+  })
+
   it('requires the same candidate signature during final revalidation', async () => {
     vi.useFakeTimers()
     const shutdown = installEligibleState(vi.fn().mockResolvedValue(undefined))
diff --git a/src/renderer/src/lib/foreground-terminal-worktrees.test.ts b/src/renderer/src/lib/foreground-terminal-worktrees.test.ts
new file mode 100644
index 00000000000..dcffad49739
--- /dev/null
+++ b/src/renderer/src/lib/foreground-terminal-worktrees.test.ts
@@ -0,0 +1,36 @@
+import { afterEach, describe, expect, it } from 'vitest'
+import {
+  getForegroundTerminalWorktreeIds,
+  registerVisibleTerminalWorktree,
+  resetForegroundTerminalWorktreeIdsForTests,
+  setForegroundTerminalWorktreeIds
+} from './foreground-terminal-worktrees'
+
+afterEach(() => {
+  resetForegroundTerminalWorktreeIdsForTests()
+})
+
+describe('foreground terminal worktrees', () => {
+  it('returns the union of explicit foreground ids and visible terminal claims', () => {
+    setForegroundTerminalWorktreeIds(['wt-explicit', null, '', undefined])
+    const unregister = registerVisibleTerminalWorktree('wt-visible')
+
+    expect(getForegroundTerminalWorktreeIds().sort()).toEqual(['wt-explicit', 'wt-visible'])
+
+    unregister()
+    expect(getForegroundTerminalWorktreeIds()).toEqual(['wt-explicit'])
+  })
+
+  it('keeps duplicate visible worktree claims until every token unregisters', () => {
+    const unregisterFirst = registerVisibleTerminalWorktree('wt-visible')
+    const unregisterSecond = registerVisibleTerminalWorktree('wt-visible')
+
+    expect(getForegroundTerminalWorktreeIds()).toEqual(['wt-visible'])
+
+    unregisterFirst()
+    expect(getForegroundTerminalWorktreeIds()).toEqual(['wt-visible'])
+
+    unregisterSecond()
+    expect(getForegroundTerminalWorktreeIds()).toEqual([])
+  })
+})
diff --git a/src/renderer/src/lib/foreground-terminal-worktrees.ts b/src/renderer/src/lib/foreground-terminal-worktrees.ts
index 6b1fa4943b1..c270f7830dd 100644
--- a/src/renderer/src/lib/foreground-terminal-worktrees.ts
+++ b/src/renderer/src/lib/foreground-terminal-worktrees.ts
@@ -1,19 +1,41 @@
-let foregroundWorktreeIds = new Set<string>()
+let explicitForegroundWorktreeIds = new Set<string>()
+const visibleTerminalClaimsByToken = new Map<symbol, string>()
 
-export function setForegroundTerminalWorktreeIds(
-  worktreeIds: Iterable<string | null | undefined>
-): void {
-  foregroundWorktreeIds = new Set(
+function normalizeWorktreeIds(worktreeIds: Iterable<string | null | undefined>): Set<string> {
+  return new Set(
     Array.from(worktreeIds).filter(
       (worktreeId): worktreeId is string => typeof worktreeId === 'string' && worktreeId.length > 0
     )
   )
 }
 
+export function setForegroundTerminalWorktreeIds(
+  worktreeIds: Iterable<string | null | undefined>
+): void {
+  explicitForegroundWorktreeIds = normalizeWorktreeIds(worktreeIds)
+}
+
+export function registerVisibleTerminalWorktree(worktreeId: string | null | undefined): () => void {
+  const normalized = normalizeWorktreeIds([worktreeId])
+  const id = Array.from(normalized)[0]
+  if (!id) {
+    return () => {}
+  }
+
+  const token = Symbol(id)
+  visibleTerminalClaimsByToken.set(token, id)
+  return () => {
+    visibleTerminalClaimsByToken.delete(token)
+  }
+}
+
 export function getForegroundTerminalWorktreeIds(): string[] {
-  return Array.from(foregroundWorktreeIds)
+  return Array.from(
+    new Set([...explicitForegroundWorktreeIds, ...visibleTerminalClaimsByToken.values()])
+  )
 }
 
 export function resetForegroundTerminalWorktreeIdsForTests(): void {
-  foregroundWorktreeIds = new Set()
+  explicitForegroundWorktreeIds = new Set()
+  visibleTerminalClaimsByToken.clear()
 }