diff --git a/src/renderer/src/components/tab-group/useTabGroupWorkspaceModel.focus.test.ts b/src/renderer/src/components/tab-group/useTabGroupWorkspaceModel.focus.test.ts
index aca20c82456..99e063b4cd7 100644
--- a/src/renderer/src/components/tab-group/useTabGroupWorkspaceModel.focus.test.ts
+++ b/src/renderer/src/components/tab-group/useTabGroupWorkspaceModel.focus.test.ts
@@ -83,7 +83,7 @@ vi.mock('../../runtime/web-runtime-terminal-creation', () => ({
 vi.mock('../../runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: mocks.isWebRuntimeSessionActive
 }))
-vi.mock('../../runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../../shared/terminal-surface-id', () => ({
   toHostSessionTabId: (tabId: string) => tabId
 }))
 
diff --git a/src/renderer/src/components/terminal-pane/pty-connection/agent-idle-working-handlers.ts b/src/renderer/src/components/terminal-pane/pty-connection/agent-idle-working-handlers.ts
index 565c4c9f5bd..be141d5d809 100644
--- a/src/renderer/src/components/terminal-pane/pty-connection/agent-idle-working-handlers.ts
+++ b/src/renderer/src/components/terminal-pane/pty-connection/agent-idle-working-handlers.ts
@@ -7,7 +7,7 @@ import { parseExecutionHostId } from '../../../../../shared/execution-host'
 import { resolveTerminalWorktreeRoute } from '@/lib/terminal-worktree-route'
 import { getConnectionId } from '@/lib/connection-context'
 import { getRemoteRuntimePtyEnvironmentId } from '@/runtime/runtime-terminal-stream'
-import { isWebTerminalSurfaceTabId } from '@/runtime/web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId } from '../../../../../shared/terminal-surface-id'
 
 import { settleTerminalPaneRecovery } from '../terminal-pane-recovery'
 import type { ConnectPanePtySession } from './connect-pane-pty-session'
diff --git a/src/renderer/src/components/terminal-pane/pty-connection/deferred-session-reattach-choice.ts b/src/renderer/src/components/terminal-pane/pty-connection/deferred-session-reattach-choice.ts
index 088b57cc532..b0b00e31446 100644
--- a/src/renderer/src/components/terminal-pane/pty-connection/deferred-session-reattach-choice.ts
+++ b/src/renderer/src/components/terminal-pane/pty-connection/deferred-session-reattach-choice.ts
@@ -1,7 +1,7 @@
 import { isRemoteRuntimePtyId } from '../../../../../shared/remote-runtime-pty-id'
 import { scheduleRuntimeGraphSync } from '@/runtime/sync-runtime-graph'
 import { useAppStore } from '@/store'
-import { isWebTerminalSurfaceTabId } from '@/runtime/web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId } from '../../../../../shared/terminal-surface-id'
 import { getEagerPtyBufferHandle } from '../pty-dispatcher'
 
 import {
diff --git a/src/renderer/src/components/terminal-pane/remote-runtime-pty-transport.ts b/src/renderer/src/components/terminal-pane/remote-runtime-pty-transport.ts
index 531c7a36482..b949ad8bd89 100644
--- a/src/renderer/src/components/terminal-pane/remote-runtime-pty-transport.ts
+++ b/src/renderer/src/components/terminal-pane/remote-runtime-pty-transport.ts
@@ -80,7 +80,10 @@ import {
 } from '@/runtime/agent-session-create-operation'
 import { replaceFitOverridePtyId, setFitOverride } from '@/lib/pane-manager/mobile-fit-overrides'
 import { replaceDriverPtyId, setDriverForPty } from '@/lib/pane-manager/mobile-driver-state'
-import { isWebTerminalSurfaceTabId, toHostSessionTabId } from '@/runtime/web-terminal-surface-id'
+import {
+  isWebTerminalSurfaceTabId,
+  toHostSessionTabId
+} from '../../../../shared/terminal-surface-id'
 import { listRemoteRuntimeSessionTabsAfterCurrentInFlight } from '@/runtime/remote-runtime-session-tabs-inflight'
 import { subscribeAcceptedWebSessionTerminalHandle } from '@/runtime/web-session-terminal-handle-events'
 import { hostSnapshotAffirmsWorktreeContents } from '@/runtime/host-session-snapshot-authority'
diff --git a/src/renderer/src/components/terminal/terminal-close-confirm-keyboard-vs-mouse.test.ts b/src/renderer/src/components/terminal/terminal-close-confirm-keyboard-vs-mouse.test.ts
index 5c6bc77e255..f8961e2bbff 100644
--- a/src/renderer/src/components/terminal/terminal-close-confirm-keyboard-vs-mouse.test.ts
+++ b/src/renderer/src/components/terminal/terminal-close-confirm-keyboard-vs-mouse.test.ts
@@ -38,7 +38,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: isWebRuntimeSessionActiveMock
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false),
   toHostSessionTabId: vi.fn((tabId: string) => tabId)
 }))
diff --git a/src/renderer/src/components/terminal/terminal-tab-actions-kill-all.test.ts b/src/renderer/src/components/terminal/terminal-tab-actions-kill-all.test.ts
index e9d01e71eca..b259954e02c 100644
--- a/src/renderer/src/components/terminal/terminal-tab-actions-kill-all.test.ts
+++ b/src/renderer/src/components/terminal/terminal-tab-actions-kill-all.test.ts
@@ -22,7 +22,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: isWebRuntimeSessionActiveMock
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../../shared/terminal-surface-id', () => ({
   toHostSessionTabId: vi.fn((tabId: string) => tabId)
 }))
 
diff --git a/src/renderer/src/components/terminal/terminal-tab-actions-unified-close.test.ts b/src/renderer/src/components/terminal/terminal-tab-actions-unified-close.test.ts
index ce1d48d3bfb..cc6357250b9 100644
--- a/src/renderer/src/components/terminal/terminal-tab-actions-unified-close.test.ts
+++ b/src/renderer/src/components/terminal/terminal-tab-actions-unified-close.test.ts
@@ -18,7 +18,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: vi.fn(() => false)
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false),
   toHostSessionTabId: vi.fn((tabId: string) => tabId)
 }))
diff --git a/src/renderer/src/components/terminal/terminal-tab-actions-unrouted-close.test.ts b/src/renderer/src/components/terminal/terminal-tab-actions-unrouted-close.test.ts
index 5f8bbc489dd..cf27db5cc07 100644
--- a/src/renderer/src/components/terminal/terminal-tab-actions-unrouted-close.test.ts
+++ b/src/renderer/src/components/terminal/terminal-tab-actions-unrouted-close.test.ts
@@ -17,7 +17,7 @@ vi.mock('@/runtime/web-runtime-session-tab-lifecycle', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: isWebRuntimeSessionActiveMock
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../../shared/terminal-surface-id', () => ({
   toHostSessionTabId: (tabId: string) => tabId
 }))
 
diff --git a/src/renderer/src/components/terminal/terminal-tab-actions.test.ts b/src/renderer/src/components/terminal/terminal-tab-actions.test.ts
index 8af23f055c8..1bb5cd76372 100644
--- a/src/renderer/src/components/terminal/terminal-tab-actions.test.ts
+++ b/src/renderer/src/components/terminal/terminal-tab-actions.test.ts
@@ -38,7 +38,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: isWebRuntimeSessionActiveMock
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: isWebTerminalSurfaceTabIdMock,
   toHostSessionTabId: toHostSessionTabIdMock
 }))
diff --git a/src/renderer/src/components/terminal/terminal-tab-actions.ts b/src/renderer/src/components/terminal/terminal-tab-actions.ts
index 37b002cdb3e..896cd860479 100644
--- a/src/renderer/src/components/terminal/terminal-tab-actions.ts
+++ b/src/renderer/src/components/terminal/terminal-tab-actions.ts
@@ -1,7 +1,7 @@
 import { useAppStore } from '@/store'
 import { closeWebRuntimeSessionTab } from '@/runtime/web-runtime-session-tab-lifecycle'
 import { isWebRuntimeSessionActive } from '@/runtime/web-runtime-session-environment'
-import { toHostSessionTabId } from '@/runtime/web-terminal-surface-id'
+import { toHostSessionTabId } from '../../../../shared/terminal-surface-id'
 import { getLatestWebSessionTabsPublicationEpoch } from '@/runtime/web-session-tabs-sync/tracking-lifecycle'
 import { resolveHostSessionTabIdForWebSessionTab } from '@/runtime/web-session-tabs-sync/tracking-mappings'
 import { resolveTerminalCloseRoute } from '@/lib/terminal-close-route'
diff --git a/src/renderer/src/components/terminal/terminal-tab-close-running-confirm.test.ts b/src/renderer/src/components/terminal/terminal-tab-close-running-confirm.test.ts
index 548cb1f792e..592d16203d4 100644
--- a/src/renderer/src/components/terminal/terminal-tab-close-running-confirm.test.ts
+++ b/src/renderer/src/components/terminal/terminal-tab-close-running-confirm.test.ts
@@ -34,7 +34,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: isWebRuntimeSessionActiveMock
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false),
   toHostSessionTabId: vi.fn((tabId: string) => tabId)
 }))
diff --git a/src/renderer/src/lib/launch-agent-in-new-tab-host-resolution.test.ts b/src/renderer/src/lib/launch-agent-in-new-tab-host-resolution.test.ts
index d42193eff51..bcdc67faeb3 100644
--- a/src/renderer/src/lib/launch-agent-in-new-tab-host-resolution.test.ts
+++ b/src/renderer/src/lib/launch-agent-in-new-tab-host-resolution.test.ts
@@ -93,7 +93,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: vi.fn(() => false)
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false)
 }))
 
diff --git a/src/renderer/src/lib/launch-agent-in-new-tab-web-runtime.test.ts b/src/renderer/src/lib/launch-agent-in-new-tab-web-runtime.test.ts
index dabdefbcefa..3fe745efeb5 100644
--- a/src/renderer/src/lib/launch-agent-in-new-tab-web-runtime.test.ts
+++ b/src/renderer/src/lib/launch-agent-in-new-tab-web-runtime.test.ts
@@ -64,7 +64,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: vi.fn(() => true)
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false)
 }))
 
diff --git a/src/renderer/src/lib/launch-agent-in-new-tab-windows-quoting.test.ts b/src/renderer/src/lib/launch-agent-in-new-tab-windows-quoting.test.ts
index 47ae2716c8b..3004cd0d268 100644
--- a/src/renderer/src/lib/launch-agent-in-new-tab-windows-quoting.test.ts
+++ b/src/renderer/src/lib/launch-agent-in-new-tab-windows-quoting.test.ts
@@ -114,7 +114,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: mockIsWebRuntimeSessionActive
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false)
 }))
 
diff --git a/src/renderer/src/lib/launch-agent-in-new-tab.test.ts b/src/renderer/src/lib/launch-agent-in-new-tab.test.ts
index 448d3dce6c0..4cedc331354 100644
--- a/src/renderer/src/lib/launch-agent-in-new-tab.test.ts
+++ b/src/renderer/src/lib/launch-agent-in-new-tab.test.ts
@@ -148,7 +148,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: mockIsWebRuntimeSessionActive
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false)
 }))
 
diff --git a/src/renderer/src/lib/launch-agent-structured-chat-guard.test.ts b/src/renderer/src/lib/launch-agent-structured-chat-guard.test.ts
index 6fbfe7ef0ee..855f8062152 100644
--- a/src/renderer/src/lib/launch-agent-structured-chat-guard.test.ts
+++ b/src/renderer/src/lib/launch-agent-structured-chat-guard.test.ts
@@ -144,7 +144,7 @@ vi.mock('@/runtime/web-runtime-terminal-creation', () => ({
 vi.mock('@/runtime/web-runtime-session-environment', () => ({
   isWebRuntimeSessionActive: vi.fn(() => false)
 }))
-vi.mock('@/runtime/web-terminal-surface-id', () => ({
+vi.mock('../../../shared/terminal-surface-id', () => ({
   isWebTerminalSurfaceTabId: vi.fn(() => false)
 }))
 vi.mock('@/lib/launch-structured-agent-session', () => {
diff --git a/src/renderer/src/lib/launch-agent-web-host-tab.ts b/src/renderer/src/lib/launch-agent-web-host-tab.ts
index 3ed58bff34b..e23851eb3b9 100644
--- a/src/renderer/src/lib/launch-agent-web-host-tab.ts
+++ b/src/renderer/src/lib/launch-agent-web-host-tab.ts
@@ -5,7 +5,7 @@ import {
   createWebRuntimeAgentSessionTerminalWithLaunchDraft,
   createWebRuntimeSessionTerminal
 } from '@/runtime/web-runtime-terminal-creation'
-import { isWebTerminalSurfaceTabId } from '@/runtime/web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId } from '../../../shared/terminal-surface-id'
 import type { AgentStartupPlan } from '@/lib/tui-agent-startup'
 import type { Tab } from '../../../shared/tab-types'
 import type { TuiAgent } from '../../../shared/tui-agent'
diff --git a/src/renderer/src/lib/web-runtime-worktree-terminal-after-wake.ts b/src/renderer/src/lib/web-runtime-worktree-terminal-after-wake.ts
index ad98e476904..d70af7f1df0 100644
--- a/src/renderer/src/lib/web-runtime-worktree-terminal-after-wake.ts
+++ b/src/renderer/src/lib/web-runtime-worktree-terminal-after-wake.ts
@@ -2,7 +2,7 @@ import { useAppStore } from '@/store'
 import { tabHasLivePty } from '@/lib/tab-has-live-pty'
 import { createWebRuntimeSessionTerminal } from '@/runtime/web-runtime-terminal-creation'
 import { isWebRuntimeSessionActive } from '@/runtime/web-runtime-session-environment'
-import { isWebTerminalSurfaceTabId } from '@/runtime/web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId } from '../../../shared/terminal-surface-id'
 import { getLastKnownHostTerminalTabCount } from '@/runtime/web-session-tabs-sync/tracking-lifecycle'
 import {
   beginWebRuntimeWakeTerminalRespawn,
diff --git a/src/renderer/src/lib/worktree-creation-agent-seeds.ts b/src/renderer/src/lib/worktree-creation-agent-seeds.ts
index e884cb38d7a..5775fdd587a 100644
--- a/src/renderer/src/lib/worktree-creation-agent-seeds.ts
+++ b/src/renderer/src/lib/worktree-creation-agent-seeds.ts
@@ -3,7 +3,7 @@ import { seedNativeChatAppliedSessionOptions } from '@/components/native-chat/na
 import { seedNativeChatLaunchDraftForAgentTab } from '@/lib/agent-launch-prompt-delivery'
 import { queueHookCommandsForFirstWorktreeTab } from '@/lib/hook-command-delayed-delivery'
 import { getRuntimeEnvironmentIdForWorktree } from '@/lib/worktree-runtime-owner'
-import { toWebTerminalSurfaceTabId } from '@/runtime/web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../shared/terminal-surface-id'
 import type { WorktreeCreationRequest } from '@/lib/pending-worktree-creation'
 import type { TuiAgent } from '../../../shared/tui-agent'
 
diff --git a/src/renderer/src/runtime/local-structured-session-tabs-host-isolation.test.ts b/src/renderer/src/runtime/local-structured-session-tabs-host-isolation.test.ts
index 61407540060..9bcf8091cb3 100644
--- a/src/renderer/src/runtime/local-structured-session-tabs-host-isolation.test.ts
+++ b/src/renderer/src/runtime/local-structured-session-tabs-host-isolation.test.ts
@@ -1,7 +1,7 @@
 import { beforeEach, describe, expect, it, vi } from 'vitest'
 import type { RuntimeMobileSessionTabsResult } from '../../../shared/runtime-types'
 import { toRuntimeExecutionHostId, toSshExecutionHostId } from '../../../shared/execution-host'
-import { toWebTerminalSurfaceTabId } from './web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../shared/terminal-surface-id'
 import {
   applyLocalStructuredSessionTabSnapshots,
   projectLocalStructuredSessionTabs
diff --git a/src/renderer/src/runtime/web-runtime-session-legacy-relay-bridged-activation.test.ts b/src/renderer/src/runtime/web-runtime-session-legacy-relay-bridged-activation.test.ts
index 6b53af0bce3..021a48b41ca 100644
--- a/src/renderer/src/runtime/web-runtime-session-legacy-relay-bridged-activation.test.ts
+++ b/src/renderer/src/runtime/web-runtime-session-legacy-relay-bridged-activation.test.ts
@@ -9,7 +9,7 @@ import {
   recordWebSessionFocusIntent,
   resetWebSessionFocusIntentForTests
 } from './web-session-focus-intent'
-import { toWebTerminalSurfaceTabId } from './web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../shared/terminal-surface-id'
 import { ENVIRONMENT_ID, WORKTREE_ID } from './web-runtime-session-test-harness'
 
 const mocks = vi.hoisted(() => ({
@@ -18,7 +18,7 @@ const mocks = vi.hoisted(() => ({
 }))
 
 vi.mock('../store', () => ({ useAppStore: { getState: mocks.getState } }))
-vi.mock('./web-session-tabs-sync', () => ({
+vi.mock('./web-session-tabs-sync/tracking-mappings', () => ({
   resolveHostSessionTabIdForWebSessionTab: mocks.resolveHostSessionTabIdForWebSessionTab
 }))
 
diff --git a/src/renderer/src/runtime/web-runtime-session-tab-activate-close.test.ts b/src/renderer/src/runtime/web-runtime-session-tab-activate-close.test.ts
index c3cbf2cb7f5..212897a9209 100644
--- a/src/renderer/src/runtime/web-runtime-session-tab-activate-close.test.ts
+++ b/src/renderer/src/runtime/web-runtime-session-tab-activate-close.test.ts
@@ -14,7 +14,7 @@ import {
   resetWebSessionCloseIntentForTests
 } from './web-session-close-intent'
 import { WEB_SESSION_TAB_RPC_TIMEOUT_MS } from './web-session-tab-rpc-timeout'
-import { toHostSessionTabId } from './web-terminal-surface-id'
+import { toHostSessionTabId } from '../../../shared/terminal-surface-id'
 import { ENVIRONMENT_ID, WORKTREE_ID, makeSnapshot } from './web-runtime-session-test-harness'
 import { stubRuntimeEnvironmentBridge } from './runtime-environment-bridge-fixture'
 
diff --git a/src/renderer/src/runtime/web-runtime-session-tab-lifecycle.ts b/src/renderer/src/runtime/web-runtime-session-tab-lifecycle.ts
index 0143417d970..69dcd50706e 100644
--- a/src/renderer/src/runtime/web-runtime-session-tab-lifecycle.ts
+++ b/src/renderer/src/runtime/web-runtime-session-tab-lifecycle.ts
@@ -17,7 +17,7 @@ import {
   recordWebSessionFocusIntent
 } from './web-session-focus-intent'
 import { WEB_SESSION_TAB_RPC_TIMEOUT_MS } from './web-session-tab-rpc-timeout'
-import { toHostSessionTabId } from './web-terminal-surface-id'
+import { toHostSessionTabId } from '../../../shared/terminal-surface-id'
 import {
   captureRuntimeEnvironmentCall,
   captureWebSessionIntentOwner,
diff --git a/src/renderer/src/runtime/web-runtime-session-tab-move.ts b/src/renderer/src/runtime/web-runtime-session-tab-move.ts
index 69640e94bf7..d33d04a74c1 100644
--- a/src/renderer/src/runtime/web-runtime-session-tab-move.ts
+++ b/src/renderer/src/runtime/web-runtime-session-tab-move.ts
@@ -10,7 +10,7 @@ import {
   clearWebSessionReorderIntent,
   recordWebSessionReorderIntent
 } from './web-session-reorder-intent'
-import { isWebTerminalSurfaceTabId, toHostSessionTabId } from './web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId, toHostSessionTabId } from '../../../shared/terminal-surface-id'
 import {
   captureRuntimeEnvironmentCall,
   captureWebSessionIntentOwner,
diff --git a/src/renderer/src/runtime/web-runtime-split-focus.ts b/src/renderer/src/runtime/web-runtime-split-focus.ts
index 8e0fc02ee83..ad7ecc9ca59 100644
--- a/src/renderer/src/runtime/web-runtime-split-focus.ts
+++ b/src/renderer/src/runtime/web-runtime-split-focus.ts
@@ -8,7 +8,7 @@ import {
   recordWebSessionFocusIntent,
   resolveWebSessionVisibleTabId
 } from './web-session-focus-intent'
-import { toHostSessionTabId, toWebTerminalSurfaceTabId } from './web-terminal-surface-id'
+import { toHostSessionTabId, toWebTerminalSurfaceTabId } from '../../../shared/terminal-surface-id'
 import type { RuntimeTerminalSplit } from '../../../shared/runtime-types'
 
 export type WebRuntimeSplitSource = { worktreeId: string; tabId: string; leafId: string }
diff --git a/src/renderer/src/runtime/web-runtime-terminal-actions.ts b/src/renderer/src/runtime/web-runtime-terminal-actions.ts
index 9ea1db698aa..33b88f8f105 100644
--- a/src/renderer/src/runtime/web-runtime-terminal-actions.ts
+++ b/src/renderer/src/runtime/web-runtime-terminal-actions.ts
@@ -9,7 +9,7 @@ import { useAppStore } from '../store'
 import { unwrapRuntimeRpcResult } from './runtime-rpc-client'
 import { parseRemoteRuntimePtyId } from './runtime-terminal-stream'
 import { toRuntimeWorktreeSelector } from './runtime-worktree-selector'
-import { isWebTerminalSurfaceTabId, toHostSessionTabId } from './web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId, toHostSessionTabId } from '../../../shared/terminal-surface-id'
 import {
   captureRuntimeEnvironmentCall,
   captureWebSessionIntentOwner,
diff --git a/src/renderer/src/runtime/web-runtime-terminal-create-operation.ts b/src/renderer/src/runtime/web-runtime-terminal-create-operation.ts
index b6664c52ce2..9a8ef12d857 100644
--- a/src/renderer/src/runtime/web-runtime-terminal-create-operation.ts
+++ b/src/renderer/src/runtime/web-runtime-terminal-create-operation.ts
@@ -20,7 +20,7 @@ import {
   recordWebSessionTerminalPlacement,
   webTerminalPlacementParentTabId
 } from './web-session-terminal-placement'
-import { toHostSessionTabId } from './web-terminal-surface-id'
+import { toHostSessionTabId } from '../../../shared/terminal-surface-id'
 import {
   captureRuntimeEnvironmentCall,
   captureWebSessionIntentOwner,
diff --git a/src/renderer/src/runtime/web-runtime-terminal-creation.ts b/src/renderer/src/runtime/web-runtime-terminal-creation.ts
index c448051a7c8..42567f76ba5 100644
--- a/src/renderer/src/runtime/web-runtime-terminal-creation.ts
+++ b/src/renderer/src/runtime/web-runtime-terminal-creation.ts
@@ -4,7 +4,7 @@ import {
   seedNativeChatLaunchDraftForAgentTab
 } from '../lib/agent-launch-prompt-delivery'
 import { createWebRuntimeSessionTerminalResult } from './web-runtime-terminal-create-operation'
-import { toWebTerminalSurfaceTabId } from './web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../shared/terminal-surface-id'
 import type {
   CreateWebRuntimeSessionTerminalArgs,
   WebRuntimeTerminalCreateOutcome
diff --git a/src/renderer/src/runtime/web-runtime-terminal-placement-settlement.ts b/src/renderer/src/runtime/web-runtime-terminal-placement-settlement.ts
index e1b10d8b5b2..d82fdcfefc6 100644
--- a/src/renderer/src/runtime/web-runtime-terminal-placement-settlement.ts
+++ b/src/renderer/src/runtime/web-runtime-terminal-placement-settlement.ts
@@ -8,7 +8,7 @@ import {
   isWebTerminalSurfaceTabId,
   toHostSessionTabId,
   toWebTerminalSurfaceTabId
-} from './web-terminal-surface-id'
+} from '../../../shared/terminal-surface-id'
 
 /** Snapshots key mirrored terminals by the parent tab, so an unknown `parent::leaf` anchor resolves to its parent. */
 function anchorUnifiedTabId(worktreeId: string, afterTabId: string): string {
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/agent-status-patch.ts b/src/renderer/src/runtime/web-session-tabs-sync/agent-status-patch.ts
index 759ac746a42..43a7158c60f 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/agent-status-patch.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/agent-status-patch.ts
@@ -5,7 +5,10 @@ import {
 import { agentEntryCompletionAt } from '../../../../shared/agent-completion-time'
 import { agentMainAgentVerdict } from '../../../../shared/agent-main-agent-verdict'
 import { normalizeCompatibleAgentStatusEntryForOwner } from '../../../../shared/agent-title-owner'
-import { isWebTerminalSurfaceTabId, toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import {
+  isWebTerminalSurfaceTabId,
+  toWebTerminalSurfaceTabId
+} from '../../../../shared/terminal-surface-id'
 import type { TerminalTab } from '../../../../shared/terminal-tab-types'
 import type {
   MirroredTerminalTab,
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/agent-status-primitives.ts b/src/renderer/src/runtime/web-session-tabs-sync/agent-status-primitives.ts
index 5009976897f..ed3aa384b9d 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/agent-status-primitives.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/agent-status-primitives.ts
@@ -3,7 +3,7 @@ import { parsePaneKey, makePaneKey, isTerminalLeafId } from '../../../../shared/
 import { isClientAuthoritativeAgentStatusPane } from '@/components/terminal-pane/renderer-owned-agent-status-registry'
 import { normalizeCompatibleAgentStatusEntryForOwner } from '../../../../shared/agent-title-owner'
 import { resolvePaneAgentOwnerRecord } from '../../../../shared/pane-agent-owner'
-import { toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../../shared/terminal-surface-id'
 import type { TerminalSurface, WebSessionTabsBatchContext, WebSessionTabsSyncState } from './state'
 import type { RetiredTerminalTabSweepState } from '../../store/slices/retired-terminal-tab-state-sweep'
 import { buildRetiredTerminalTabStateSweepPatch } from '../../store/slices/retired-terminal-tab-state-sweep'
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-base.ts b/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-base.ts
index 402e9383e88..65166ab8e79 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-base.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-base.ts
@@ -21,7 +21,7 @@ import {
   clearWebAgentSessionHandoff
 } from '../web-agent-session-handoff'
 import { toRemoteRuntimePtyId } from '../runtime-terminal-stream'
-import { toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../../shared/terminal-surface-id'
 import {
   isReadyTerminalTab,
   isTerminalSurfaceTab,
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-groups.ts b/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-groups.ts
index 0c6100c5cff..8cd51151198 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-groups.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-groups.ts
@@ -1,6 +1,6 @@
 import type { TabGroup } from '../../../../shared/tab-types'
 import type { prepareWebSessionTabsSnapshotUnified } from './apply-preparation-unified'
-import { toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../../shared/terminal-surface-id'
 import {
   isWebSessionBrowserPlacementGroupReserved,
   peekWebSessionBrowserPlacementGroup
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-unified.ts b/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-unified.ts
index acafe619e28..7b4b66673ce 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-unified.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/apply-preparation-unified.ts
@@ -1,7 +1,7 @@
 import type { prepareWebSessionTabsSnapshotBrowser } from './apply-preparation-browser'
 import { buildTerminalUnifiedTab } from './tab-builders'
 import { isAgentSessionTab } from './terminal-surfaces'
-import { toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../../shared/terminal-surface-id'
 import {
   resolveWebSessionSiblingVisibleTabId,
   resolveWebSessionVisibleTabId
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/layout-groups.ts b/src/renderer/src/runtime/web-session-tabs-sync/layout-groups.ts
index 3942b22b934..78b4f54d913 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/layout-groups.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/layout-groups.ts
@@ -7,7 +7,7 @@ import type {
   MirroredEditorTab,
   TerminalSurface
 } from './state'
-import { toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../../shared/terminal-surface-id'
 import { clearHostSessionTabIdMappings, setHostSessionTabIdMapping } from './tracking-mappings'
 import { isWebSessionBrowserPlacementGroupReserved } from '../web-session-browser-placement'
 import { resolveWebSessionReorderedOrder } from '../web-session-reorder-intent'
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/mirrored-terminal-recovery-ledger.test.ts b/src/renderer/src/runtime/web-session-tabs-sync/mirrored-terminal-recovery-ledger.test.ts
index d1992a27030..b62542a86cd 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/mirrored-terminal-recovery-ledger.test.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/mirrored-terminal-recovery-ledger.test.ts
@@ -2,7 +2,7 @@ import { describe, expect, it } from 'vitest'
 import type { RuntimeMobileSessionTabsResult } from '../../../../shared/runtime-types'
 import type { TerminalTab, TerminalTabRecoveryLedger } from '../../../../shared/terminal-tab-types'
 import { buildMirroredTerminalTabs } from './terminal-build'
-import { toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../../shared/terminal-surface-id'
 
 /**
  * The recovery ledger is client-local. The host publishes no such field, so a
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/terminal-build.ts b/src/renderer/src/runtime/web-session-tabs-sync/terminal-build.ts
index 8c227758aca..7ae2941cbaa 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/terminal-build.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/terminal-build.ts
@@ -4,7 +4,7 @@ import { normalizeTerminalLayoutPtyOwnership } from '@/components/terminal-pane/
 import { resolvePaneAgentOwnerRecord } from '../../../../shared/pane-agent-owner'
 import { normalizeCompatibleAgentTitleForOwner } from '../../../../shared/agent-title-owner'
 import { getRemoteRuntimePtyEnvironmentId, toRemoteRuntimePtyId } from '../runtime-terminal-stream'
-import { toWebTerminalSurfaceTabId } from '../web-terminal-surface-id'
+import { toWebTerminalSurfaceTabId } from '../../../../shared/terminal-surface-id'
 import type { MirroredTerminalTab, TerminalSurface, ReadyTerminalSurface } from './state'
 import { chooseRemoteTerminalLayout, isTerminalSurfaceTab } from './terminal-surfaces'
 
diff --git a/src/renderer/src/runtime/web-session-tabs-sync/terminal-surfaces.ts b/src/renderer/src/runtime/web-session-tabs-sync/terminal-surfaces.ts
index 759fedfbc0e..445950ce97b 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync/terminal-surfaces.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync/terminal-surfaces.ts
@@ -12,7 +12,7 @@ import {
   HOST_TERMINAL_SURFACE_SEPARATOR,
   WEB_TERMINAL_SURFACE_TAB_PREFIX,
   toWebTerminalSurfaceTabId
-} from '../web-terminal-surface-id'
+} from '../../../../shared/terminal-surface-id'
 import type {
   ReadyBrowserSurface,
   ReadyEditorSurface,
diff --git a/src/renderer/src/runtime/web-session-terminal-orphan-recovery-surface.ts b/src/renderer/src/runtime/web-session-terminal-orphan-recovery-surface.ts
index e54b9329bd4..c8387979542 100644
--- a/src/renderer/src/runtime/web-session-terminal-orphan-recovery-surface.ts
+++ b/src/renderer/src/runtime/web-session-terminal-orphan-recovery-surface.ts
@@ -7,7 +7,7 @@ import type {
 } from '../../../shared/runtime-types'
 import type { TerminalTab } from '../../../shared/terminal-tab-types'
 import { parseRemoteRuntimePtyId } from './runtime-terminal-stream'
-import { isWebTerminalSurfaceTabId, toHostSessionTabId } from './web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId, toHostSessionTabId } from '../../../shared/terminal-surface-id'
 import {
   hasTerminalHandleRetirementProof,
   isRemovedSnapshot,
diff --git a/src/renderer/src/runtime/web-session-terminal-orphan-recovery.ts b/src/renderer/src/runtime/web-session-terminal-orphan-recovery.ts
index 62180292b89..9a4e3b983ee 100644
--- a/src/renderer/src/runtime/web-session-terminal-orphan-recovery.ts
+++ b/src/renderer/src/runtime/web-session-terminal-orphan-recovery.ts
@@ -43,7 +43,7 @@ import {
   clearTerminalRecoveryRpcLaneForTests,
   runInTerminalRecoveryRpcLane
 } from './web-session-terminal-orphan-recovery-rpc-lane'
-import { isWebTerminalSurfaceTabId, toHostSessionTabId } from './web-terminal-surface-id'
+import { isWebTerminalSurfaceTabId, toHostSessionTabId } from '../../../shared/terminal-surface-id'
 import { buildWebTerminalOrphanTopologyProposal } from './web-session-terminal-orphan-topology'
 import {
   clearRetainedTerminalRetirementProofsForTests,
diff --git a/src/renderer/src/runtime/web-session-terminal-orphan-topology.ts b/src/renderer/src/runtime/web-session-terminal-orphan-topology.ts
index 8251bf19df5..ad259da2c65 100644
--- a/src/renderer/src/runtime/web-session-terminal-orphan-topology.ts
+++ b/src/renderer/src/runtime/web-session-terminal-orphan-topology.ts
@@ -5,7 +5,7 @@ import type {
   TerminalPaneLayoutNode,
   TerminalTab
 } from '../../../shared/terminal-tab-types'
-import { toHostSessionTabId } from './web-terminal-surface-id'
+import { toHostSessionTabId } from '../../../shared/terminal-surface-id'
 
 export type WebTerminalOrphanTopologyState = {
   terminalLayoutsByTabId: Record<string, TerminalLayoutSnapshot>
diff --git a/src/renderer/src/runtime/web-terminal-surface-id.ts b/src/renderer/src/runtime/web-terminal-surface-id.ts
deleted file mode 100644
index f887a194d59..00000000000
--- a/src/renderer/src/runtime/web-terminal-surface-id.ts
+++ /dev/null
@@ -1,7 +0,0 @@
-export {
-  HOST_TERMINAL_SURFACE_SEPARATOR,
-  isWebTerminalSurfaceTabId,
-  toHostSessionTabId,
-  toWebTerminalSurfaceTabId,
-  WEB_TERMINAL_SURFACE_TAB_PREFIX
-} from '../../../shared/terminal-surface-id'