diff --git a/docs/reference/remote-wire-compatibility.md b/docs/reference/remote-wire-compatibility.md
index 1fceb67d5d5..8a27345bdc0 100644
--- a/docs/reference/remote-wire-compatibility.md
+++ b/docs/reference/remote-wire-compatibility.md
@@ -242,3 +242,23 @@ predicate. It is unobservable today — the host publishes neither field for a c
 all, so a mirror has nothing to take either way. If the capability-gated publish this section
 anticipates ever lands, narrow them the same way rather than by placement kind: a mirror should
 take a failure it cannot otherwise see, and only the hosting client should refuse it.
+
+## Who names a structured chat tab
+
+`RuntimeMobileSessionAgentTab.providerSessionId` is Rule 1: an optional field naming the Codex
+thread the session currently writes to (the head of the record's provider-handle chain). An old
+host omits it and the chat keeps the generic label; an old client ignores it. The field is
+identity, not a name — the name is read from the provider by the AI Vault title pipeline on the
+host that owns the session, which is why a remote structured chat resolves against that host's
+Codex home rather than the client's.
+
+Absence is unknown, never "no thread". The host publishes the key only once the provider has
+proven a handle, and a blank string would ask the title pipeline to name a conversation that has
+no name yet. A late-proven thread reaches clients through a republished snapshot, so the tab is
+named without waiting for a restart.
+
+The name itself is client-owned, the same shape as the browser-tab carve-out above. A host
+snapshot carries no `customLabel` and no `aiVaultTitle`, so the mirror in `web-session-tabs-sync.ts`
+preserves both from the tab it is replacing. Dropping either one renames the tab back to the
+generic label on the next snapshot and takes the user's own rename with it. The cross-version
+harness does not exercise the session-tab sync channel, so nothing fails if this is forgotten.
diff --git a/src/main/native-chat/agent-session-wire/structured-provider-session-ownership.ts b/src/main/native-chat/agent-session-wire/structured-provider-session-ownership.ts
index ad211902433..ed6f7b9c2b9 100644
--- a/src/main/native-chat/agent-session-wire/structured-provider-session-ownership.ts
+++ b/src/main/native-chat/agent-session-wire/structured-provider-session-ownership.ts
@@ -1,3 +1,4 @@
+import { agentSessionProviderHandleChainHead } from '../../../shared/agent-session-provider-handle'
 import type { AgentSessionLease, AgentSessionRecord } from '../../../shared/agent-session-record'
 
 export type StructuredProviderSessionOwnership = {
@@ -22,3 +23,16 @@ export function listStructuredProviderSessionOwnership(
     }))
   )
 }
+
+/**
+ * Provider conversation the session currently writes to, or null while the provider has not proven
+ * one. Only the chain head counts: an earlier link names a conversation this session has moved on
+ * from, and a fork's root is a different conversation entirely.
+ */
+export function headStructuredProviderSessionId(record: AgentSessionRecord): string | null {
+  const handle = agentSessionProviderHandleChainHead(record.providerHandleChain)?.handle
+  if (!handle) {
+    return null
+  }
+  return handle.provider === 'codex' ? handle.threadId : handle.sessionId
+}
diff --git a/src/main/runtime/orca-runtime-structured-session-restore.test.ts b/src/main/runtime/orca-runtime-structured-session-restore.test.ts
index 39275ebedc1..f3ab3942b02 100644
--- a/src/main/runtime/orca-runtime-structured-session-restore.test.ts
+++ b/src/main/runtime/orca-runtime-structured-session-restore.test.ts
@@ -124,6 +124,7 @@ describe('structured session cold restoration', () => {
     internal.refreshMobileSessionPtyRecords = async () => new Set()
     internal.ensureStructuredAgentSessionHost = async () => undefined
     setStructuredAgentSessionHost({
+      deps: { store: { getRecord: () => null } },
       reconcileRestartLeases: async () => undefined,
       restoreReadableSessions: async () => undefined,
       listSessionTabs: () => [
diff --git a/src/main/runtime/orca-runtime.ts b/src/main/runtime/orca-runtime.ts
index 3fd419cb69b..a6ae79e1e04 100644
--- a/src/main/runtime/orca-runtime.ts
+++ b/src/main/runtime/orca-runtime.ts
@@ -288,6 +288,7 @@ import { shouldForwardHeadlessTerminalQueryReply } from './headless-terminal-que
 import type { TerminalRevealIdentity } from '../../shared/terminal-reveal-identity'
 import { structuredAgentSessionTabId } from '../../shared/structured-agent-session-projection'
 import { collectSavedStructuredAgentSessionIds } from './saved-structured-agent-session-restoration'
+import { headStructuredProviderSessionId } from '../native-chat/agent-session-wire/structured-provider-session-ownership'
 import type {
   OrchestrationCompatibilityEvidence,
   OrchestrationCompatibilityHostStamp
@@ -12346,6 +12347,12 @@ export class OrcaRuntimeService {
     }
   }
 
+  /** Codex thread behind a structured session, or null while the provider has not proven one. */
+  private structuredAgentSessionProviderSessionId(sessionId: string): string | null {
+    const record = getStructuredAgentSessionHost()?.deps.store.getRecord(sessionId) ?? null
+    return record ? headStructuredProviderSessionId(record) : null
+  }
+
   publishStructuredAgentSessionTab(input: {
     workspaceId: string
     sessionId: string
@@ -12355,7 +12362,14 @@ export class OrcaRuntimeService {
   }): void {
     const existing = this.mobileSessionTabsByWorktree.get(input.workspaceId)
     const id = `agent-session:${input.sessionId}`
+    const providerSessionId = this.structuredAgentSessionProviderSessionId(input.sessionId)
     if (existing?.tabs.some((tab) => tab.id === id)) {
+      this.republishStructuredAgentSessionProviderSessionId({
+        existing,
+        id,
+        providerSessionId,
+        notify: input.notify
+      })
       return
     }
     const tab: RuntimeMobileSessionAgentTab = {
@@ -12364,6 +12378,9 @@ export class OrcaRuntimeService {
       title: 'Codex Chat',
       sessionId: input.sessionId,
       agent: input.agent,
+      // Why: omit rather than blank — an unproven identity is unknown, and an empty id would ask
+      // the title pipeline to name a conversation that has no name yet.
+      ...(providerSessionId ? { providerSessionId } : {}),
       isActive: input.activate
     }
     const tabs = [...(existing?.tabs ?? [])].map((candidate) => ({
@@ -12407,6 +12424,38 @@ export class OrcaRuntimeService {
     }
   }
 
+  /** A thread proven after the tab was published (or replaced by a resume) still has to reach the
+   *  client, or the chat keeps the generic name for the life of the session. */
+  private republishStructuredAgentSessionProviderSessionId(input: {
+    existing: RuntimeMobileSessionTabsSnapshot
+    id: string
+    providerSessionId: string | null
+    notify?: boolean
+  }): void {
+    const current = input.existing.tabs.find(
+      (tab): tab is RuntimeMobileSessionAgentTab =>
+        tab.type === 'agent-session' && tab.id === input.id
+    )
+    if (
+      !current ||
+      !input.providerSessionId ||
+      current.providerSessionId === input.providerSessionId
+    ) {
+      return
+    }
+    const snapshot: RuntimeMobileSessionTabsSnapshot = {
+      ...input.existing,
+      snapshotVersion: input.existing.snapshotVersion + 1,
+      tabs: input.existing.tabs.map((tab) =>
+        tab.id === input.id ? { ...tab, providerSessionId: input.providerSessionId! } : tab
+      )
+    }
+    this.mobileSessionTabsByWorktree.set(snapshot.worktree, snapshot)
+    if (input.notify !== false) {
+      this.emitMobileSessionTabsSnapshot(snapshot)
+    }
+  }
+
   private async resolveRuntimeGitTarget(worktreeSelector: string): Promise<{
     worktree: ResolvedWorktree
     repo?: Repo
diff --git a/src/main/runtime/structured-agent-session-tab-provider-session.test.ts b/src/main/runtime/structured-agent-session-tab-provider-session.test.ts
new file mode 100644
index 00000000000..2295ff2d561
--- /dev/null
+++ b/src/main/runtime/structured-agent-session-tab-provider-session.test.ts
@@ -0,0 +1,131 @@
+import { afterEach, describe, expect, it } from 'vitest'
+import {
+  AGENT_SESSION_RECORD_SCHEMA_VERSION,
+  type AgentSessionRecord
+} from '../../shared/agent-session-record'
+import {
+  agentSessionProviderHandleKey,
+  appendAgentSessionProviderHandleLink,
+  type AgentSessionProviderHandleLink
+} from '../../shared/agent-session-provider-handle'
+import { agentSessionLeaseFixture } from '../../shared/agent-session-record.test-fixture'
+import { setStructuredAgentSessionHost } from '../native-chat/agent-session-wire/structured-agent-session-registry'
+import { OrcaRuntimeService } from './orca-runtime'
+
+afterEach(() => setStructuredAgentSessionHost(null))
+
+function codexLink(threadId: string, linkId: string): AgentSessionProviderHandleLink {
+  return {
+    linkId,
+    origin: 'created',
+    mintedAtFence: 7,
+    observedAt: 1_000,
+    handle: { provider: 'codex', threadId }
+  }
+}
+
+function codexRecord(chain: AgentSessionProviderHandleLink[]): AgentSessionRecord {
+  return {
+    schemaVersion: AGENT_SESSION_RECORD_SCHEMA_VERSION,
+    sessionId: 'session-1',
+    location: {
+      executionHostId: 'local',
+      wslDistro: null,
+      workspaceId: 'workspace-1',
+      workspaceKind: 'git-worktree'
+    },
+    provider: 'codex',
+    providerHandleChain: chain,
+    accountHome: { variable: 'CODEX_HOME', path: '/home/user/.codex' },
+    lease: agentSessionLeaseFixture({ sessionId: 'session-1' }),
+    createdAt: 1,
+    updatedAt: 2
+  }
+}
+
+function installHost(recordsBySessionId: Record<string, AgentSessionRecord | null>): void {
+  setStructuredAgentSessionHost({
+    deps: { store: { getRecord: (id: string) => recordsBySessionId[id] ?? null } }
+  } as never)
+}
+
+async function publishedAgentTab(
+  runtime: OrcaRuntimeService
+): Promise<{ providerSessionId?: string } | undefined> {
+  const snapshot = await runtime.listMobileSessionTabs('id:workspace-1')
+  return snapshot.tabs.find((tab) => tab.type === 'agent-session') as
+    | { providerSessionId?: string }
+    | undefined
+}
+
+describe('structured chat tab provider session identity', () => {
+  it('publishes the Codex thread the session is bound to', async () => {
+    installHost({ 'session-1': codexRecord([codexLink('thread-1', 'link-1')]) })
+    const runtime = new OrcaRuntimeService()
+
+    runtime.publishStructuredAgentSessionTab({
+      workspaceId: 'workspace-1',
+      sessionId: 'session-1',
+      agent: 'codex',
+      activate: true
+    })
+
+    expect((await publishedAgentTab(runtime))?.providerSessionId).toBe('thread-1')
+  })
+
+  it('publishes no identity while the provider has not proven one', async () => {
+    installHost({ 'session-1': codexRecord([]) })
+    const runtime = new OrcaRuntimeService()
+
+    runtime.publishStructuredAgentSessionTab({
+      workspaceId: 'workspace-1',
+      sessionId: 'session-1',
+      agent: 'codex',
+      activate: true
+    })
+
+    const tab = await publishedAgentTab(runtime)
+    expect(tab).toBeDefined()
+    expect(tab).not.toHaveProperty('providerSessionId')
+  })
+
+  it('carries a thread proven after the tab was already published', async () => {
+    const records: Record<string, AgentSessionRecord> = { 'session-1': codexRecord([]) }
+    installHost(records)
+    const runtime = new OrcaRuntimeService()
+    runtime.publishStructuredAgentSessionTab({
+      workspaceId: 'workspace-1',
+      sessionId: 'session-1',
+      agent: 'codex',
+      activate: true
+    })
+
+    records['session-1'] = codexRecord([codexLink('thread-1', 'link-1')])
+    runtime.publishStructuredAgentSessionTab({
+      workspaceId: 'workspace-1',
+      sessionId: 'session-1',
+      agent: 'codex',
+      activate: false
+    })
+
+    expect((await publishedAgentTab(runtime))?.providerSessionId).toBe('thread-1')
+  })
+
+  it('names the conversation the session writes to now, not the one it forked from', async () => {
+    const chain = appendAgentSessionProviderHandleLink([codexLink('thread-old', 'link-1')], {
+      ...codexLink('thread-new', 'link-2'),
+      origin: 'forked',
+      forkedFromKey: agentSessionProviderHandleKey({ provider: 'codex', threadId: 'thread-old' })
+    })
+    installHost({ 'session-1': codexRecord(chain) })
+    const runtime = new OrcaRuntimeService()
+    runtime.publishStructuredAgentSessionTab({
+      workspaceId: 'workspace-1',
+      sessionId: 'session-1',
+      agent: 'codex',
+      activate: true
+    })
+
+    expect((await publishedAgentTab(runtime))?.providerSessionId).toBe('thread-new')
+  })
+})
diff --git a/src/renderer/src/lib/ai-vault-tab-title-requests.ts b/src/renderer/src/lib/ai-vault-tab-title-requests.ts
index 1efeb48e001..50ec2795f1c 100644
--- a/src/renderer/src/lib/ai-vault-tab-title-requests.ts
+++ b/src/renderer/src/lib/ai-vault-tab-title-requests.ts
@@ -4,6 +4,7 @@ import type { AiVaultSessionTitle } from '../../../shared/ai-vault-session-title
 import { isAiVaultTitleAgent } from '../../../shared/ai-vault-session-title'
 import type { ExecutionHostId } from '../../../shared/execution-host'
 import { parsePaneKey } from '../../../shared/stable-pane-id'
+import type { Tab } from '../../../shared/tab-types'
 import type { TerminalTab } from '../../../shared/terminal-tab-types'
 import { getExecutionHostIdForWorktree } from '@/lib/worktree-runtime-owner'
 import type { AppState } from '@/store/types'
@@ -67,6 +68,35 @@ function registerCandidate(
   })
 }
 
+/** Structured chat tabs the host has given a provider conversation id. */
+export function structuredAgentSessionTitleTabs(state: AppState): Tab[] {
+  return Object.values(state.unifiedTabsByWorktree)
+    .flat()
+    .filter(
+      (tab) =>
+        tab.contentType === 'agent-session' &&
+        isAiVaultTitleAgent(tab.agentSessionAgent) &&
+        Boolean(tab.agentSessionProviderSessionId)
+    )
+}
+
+/**
+ * Where a tab's currently stored provider name lives, across both tab models. The sync compares
+ * against this to decide whether a request still needs a scan, so it has to see chat tabs too.
+ */
+export function aiVaultTitleByTabId(
+  state: AppState
+): Map<string, AiVaultSessionTitle | null | undefined> {
+  const titles = new Map<string, AiVaultSessionTitle | null | undefined>()
+  for (const tab of Object.values(state.tabsByWorktree).flat()) {
+    titles.set(tab.id, tab.aiVaultTitle)
+  }
+  for (const tab of structuredAgentSessionTitleTabs(state)) {
+    titles.set(tab.id, tab.aiVaultTitle)
+  }
+  return titles
+}
+
 export function collectAiVaultTitleRequests(state: AppState): AiVaultTitleRequest[] {
   const tabsById = new Map(
     Object.values(state.tabsByWorktree)
@@ -109,5 +139,18 @@ export function collectAiVaultTitleRequests(state: AppState): AiVaultTitleReques
     })
   }
 
-  return [...candidates.values()].map(({ priority: _priority, ...request }) => request)
+  const requests = [...candidates.values()].map(({ priority: _priority, ...request }) => request)
+  for (const tab of structuredAgentSessionTitleTabs(state)) {
+    requests.push({
+      agent: tab.agentSessionAgent as AiVaultSessionTitle['agent'],
+      executionHostId: getExecutionHostIdForWorktree(state, tab.worktreeId),
+      providerSession: { key: 'session_id', id: tab.agentSessionProviderSessionId! },
+      // Why: a chat the user is holding open is live, so its provider name is re-read on the same
+      // cadence a terminal-backed session gets — that is how a later rename reaches the tab.
+      refresh: true,
+      tabId: tab.id,
+      worktreeId: tab.worktreeId
+    })
+  }
+  return requests
 }
diff --git a/src/renderer/src/lib/ai-vault-tab-title-sync-inputs.ts b/src/renderer/src/lib/ai-vault-tab-title-sync-inputs.ts
index 569d79b0dc8..3a3867e0621 100644
--- a/src/renderer/src/lib/ai-vault-tab-title-sync-inputs.ts
+++ b/src/renderer/src/lib/ai-vault-tab-title-sync-inputs.ts
@@ -3,7 +3,10 @@ import { isAiVaultTitleAgent } from '../../../shared/ai-vault-session-title'
 import type { TerminalTab } from '../../../shared/terminal-tab-types'
 import { getExecutionHostIdForWorktree } from '@/lib/worktree-runtime-owner'
 import type { AppState } from '@/store/types'
-import { collectAiVaultTitleRequests } from './ai-vault-tab-title-requests'
+import {
+  collectAiVaultTitleRequests,
+  structuredAgentSessionTitleTabs
+} from './ai-vault-tab-title-requests'
 
 function providerSessionEqual(
   left: AgentProviderSessionMetadata | undefined,
@@ -130,6 +133,24 @@ function terminalTabsEqual(current: AppState, previous: AppState): boolean {
   return true
 }
 
+function structuredChatTabsEqual(current: AppState, previous: AppState): boolean {
+  const currentTabs = structuredAgentSessionTitleTabs(current)
+  const previousTabs = structuredAgentSessionTitleTabs(previous)
+  if (currentTabs.length !== previousTabs.length) {
+    return false
+  }
+  return currentTabs.every((tab, index) => {
+    const other = previousTabs[index]!
+    return (
+      tab.id === other.id &&
+      tab.worktreeId === other.worktreeId &&
+      tab.agentSessionAgent === other.agentSessionAgent &&
+      tab.agentSessionProviderSessionId === other.agentSessionProviderSessionId &&
+      titleEqual(tab.aiVaultTitle, other.aiVaultTitle)
+    )
+  })
+}
+
 function activePanesEqual(current: AppState, previous: AppState): boolean {
   const currentKeys = Object.keys(current.terminalLayoutsByTabId)
   const previousKeys = Object.keys(previous.terminalLayoutsByTabId)
@@ -169,6 +190,12 @@ export function aiVaultTitleSyncInputsChanged(current: AppState, previous: AppSt
   if (current.tabsByWorktree !== previous.tabsByWorktree && !terminalTabsEqual(current, previous)) {
     return true
   }
+  if (
+    current.unifiedTabsByWorktree !== previous.unifiedTabsByWorktree &&
+    !structuredChatTabsEqual(current, previous)
+  ) {
+    return true
+  }
   if (
     current.terminalLayoutsByTabId !== previous.terminalLayoutsByTabId &&
     !activePanesEqual(current, previous)
diff --git a/src/renderer/src/lib/ai-vault-tab-title-sync.test.ts b/src/renderer/src/lib/ai-vault-tab-title-sync.test.ts
index a062b9df906..7e29098dcde 100644
--- a/src/renderer/src/lib/ai-vault-tab-title-sync.test.ts
+++ b/src/renderer/src/lib/ai-vault-tab-title-sync.test.ts
@@ -81,6 +81,7 @@ function makeState(args: {
         }
       : {},
     tabsByWorktree: { [args.worktreeId]: [tab] },
+    unifiedTabsByWorktree: {},
     terminalLayoutsByTabId: {
       'tab-1': {
         root: { type: 'leaf', leafId: 'leaf-1' },
diff --git a/src/renderer/src/lib/ai-vault-tab-title-sync.ts b/src/renderer/src/lib/ai-vault-tab-title-sync.ts
index bac035ff265..44a6ba0eae3 100644
--- a/src/renderer/src/lib/ai-vault-tab-title-sync.ts
+++ b/src/renderer/src/lib/ai-vault-tab-title-sync.ts
@@ -4,6 +4,7 @@ import type {
 } from '../../../shared/ai-vault-session-title'
 import type { AppState } from '@/store/types'
 import {
+  aiVaultTitleByTabId,
   collectAiVaultTitleRequests,
   type AiVaultTitleRequest
 } from './ai-vault-tab-title-requests'
@@ -43,13 +44,9 @@ function nextLiveRefreshDelay(state: AppState, requests: AiVaultTitleRequest[]):
   if (liveRequests.length === 0) {
     return null
   }
-  const tabsById = new Map(
-    Object.values(state.tabsByWorktree)
-      .flat()
-      .map((tab) => [tab.id, tab] as const)
-  )
+  const storedTitleByTabId = aiVaultTitleByTabId(state)
   const hasMissingTitle = liveRequests.some((request) => {
-    const stored = tabsById.get(request.tabId)?.aiVaultTitle
+    const stored = storedTitleByTabId.get(request.tabId)
     return (
       stored?.agent !== request.agent ||
       stored.sessionId !== request.providerSession.id ||
@@ -141,14 +138,10 @@ export function startAiVaultTabTitleSync(dependencies: SyncDependencies): () =>
     }
 
     const state = dependencies.getState()
-    const tabsById = new Map(
-      Object.values(state.tabsByWorktree)
-        .flat()
-        .map((tab) => [tab.id, tab] as const)
-    )
+    const storedTitleByTabId = aiVaultTitleByTabId(state)
     const requests = collectAiVaultTitleRequests(state)
     const requestsToScan = requests.filter((request) => {
-      const stored = tabsById.get(request.tabId)?.aiVaultTitle
+      const stored = storedTitleByTabId.get(request.tabId)
       const identityMatches =
         stored?.agent === request.agent && stored.sessionId === request.providerSession.id
       if (stored && !identityMatches) {
diff --git a/src/renderer/src/lib/structured-agent-session-tab-title.test.ts b/src/renderer/src/lib/structured-agent-session-tab-title.test.ts
new file mode 100644
index 00000000000..898a804447f
--- /dev/null
+++ b/src/renderer/src/lib/structured-agent-session-tab-title.test.ts
@@ -0,0 +1,345 @@
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import type {
+  AiVaultSessionTitlesArgs,
+  AiVaultSessionTitlesResult
+} from '../../../shared/ai-vault-session-title'
+import type { RuntimeMobileSessionTabsResult } from '../../../shared/runtime-types'
+import type { Tab } from '../../../shared/tab-types'
+import { resolveUnifiedTabLabel } from '../../../shared/tab-title-resolution'
+import { workspaceSessionStateSchema } from '../../../shared/workspace-session-schema'
+import type { WorkspaceSessionState } from '../../../shared/workspace-session-state-types'
+import {
+  applyLocalStructuredSessionTabSnapshots,
+  LOCAL_STRUCTURED_SESSION_OWNER
+} from '../runtime/local-structured-session-tabs-sync'
+import { resetWebSessionTabsSnapshotFreshnessForTests } from '../runtime/web-session-tabs-sync'
+import { patchTab } from '../store/slices/tab-group-state'
+import { buildHydratedTabState } from '../store/slices/tabs-hydration'
+import { applyAgentSessionAiVaultTitle } from '../store/slices/agent-session-tab-ai-vault-title'
+import { buildPersistedUnifiedTabSessionData } from './workspace-session-unified-tabs'
+import { startAiVaultTabTitleSync } from './ai-vault-tab-title-sync'
+import type { AppState } from '@/store/types'
+
+const WORKTREE_ID = 'repo-1::worktree-1'
+const GROUP_ID = 'group-1'
+
+afterEach(() => {
+  resetWebSessionTabsSnapshotFreshnessForTests()
+})
+
+type SessionSpec = { sessionId: string; providerSessionId?: string; title?: string }
+
+function hostSnapshot(
+  epoch: string,
+  snapshotVersion: number,
+  sessions: readonly SessionSpec[]
+): RuntimeMobileSessionTabsResult {
+  const tabIds = sessions.map((session) => `agent-session:${session.sessionId}`)
+  return {
+    worktree: WORKTREE_ID,
+    publicationEpoch: epoch,
+    snapshotVersion,
+    activeGroupId: GROUP_ID,
+    activeTabId: tabIds[0] ?? null,
+    activeTabType: 'agent-session',
+    tabGroups: [{ id: GROUP_ID, activeTabId: tabIds[0] ?? null, tabOrder: tabIds }],
+    tabs: sessions.map((session, index) => ({
+      type: 'agent-session' as const,
+      id: tabIds[index]!,
+      title: session.title ?? 'Codex Chat',
+      sessionId: session.sessionId,
+      agent: 'codex' as const,
+      ...(session.providerSessionId ? { providerSessionId: session.providerSessionId } : {}),
+      isActive: index === 0
+    }))
+  }
+}
+
+function emptyState(): AppState {
+  return {
+    activeBrowserTabId: null,
+    activeBrowserTabIdByWorktree: {},
+    activeFileId: null,
+    activeFileIdByWorktree: {},
+    activeGroupIdByWorktree: { [WORKTREE_ID]: GROUP_ID },
+    activeTabId: null,
+    activeTabIdByWorktree: {},
+    activeTabType: null,
+    activeTabTypeByWorktree: {},
+    activeWorktreeId: WORKTREE_ID,
+    agentStatusByPaneKey: {},
+    agentStatusEpoch: 0,
+    browserCertificateFailuresByPageId: {},
+    browserPagesByWorkspace: {},
+    browserTabsByWorktree: {},
+    detectedWorktreesByRepo: {},
+    folderWorkspaces: [],
+    getKnownWorktreeById: () => ({ path: '/workspace/repo-1' }),
+    groupsByWorktree: { [WORKTREE_ID]: [] },
+    layoutByWorktree: {},
+    openFiles: [],
+    ptyIdsByTabId: {},
+    remoteBrowserPageHandlesByPageId: {},
+    repos: [],
+    retainedAgentsByPaneKey: {},
+    sleepingAgentSessionsByPaneKey: {},
+    sortEpoch: 0,
+    tabBarOrderByWorktree: {},
+    tabsByWorktree: {},
+    terminalLayoutsByTabId: {},
+    unifiedTabsByWorktree: {},
+    unreadTerminalTabs: {},
+    worktreesByRepo: {}
+  } as unknown as AppState
+}
+
+let epochCounter = 0
+
+function makeStore() {
+  const epoch = `epoch-${(epochCounter += 1)}`
+  const listeners = new Set<(next: AppState, previous: AppState) => void>()
+  const labelHistory: string[] = []
+  let state = emptyState()
+  const commit = (next: AppState): void => {
+    if (next === state) {
+      return
+    }
+    const previous = state
+    state = next
+    const tab = chatTabs(state)[0]
+    if (tab) {
+      labelHistory.push(resolveUnifiedTabLabel(tab, false, 'Codex Chat'))
+    }
+    for (const listener of listeners) {
+      listener(state, previous)
+    }
+  }
+  // Why: the real store action, so a test cannot pass on a hand-written title write.
+  state = {
+    ...state,
+    setAiVaultTabTitle: (tabId: string, aiVaultTitle: Tab['aiVaultTitle'] | null) => {
+      const patched = applyAgentSessionAiVaultTitle(
+        state.unifiedTabsByWorktree,
+        tabId,
+        aiVaultTitle ?? null
+      )
+      if (patched) {
+        commit({ ...state, unifiedTabsByWorktree: patched })
+      }
+    }
+  } as AppState
+  return {
+    getState: () => state,
+    labelHistory,
+    subscribe: (listener: (next: AppState, previous: AppState) => void) => {
+      listeners.add(listener)
+      return () => listeners.delete(listener)
+    },
+    publish: (snapshotVersion: number, sessions: readonly SessionSpec[]) => {
+      commit(
+        applyLocalStructuredSessionTabSnapshots(
+          state,
+          [hostSnapshot(epoch, snapshotVersion, sessions)],
+          LOCAL_STRUCTURED_SESSION_OWNER
+        ) as AppState
+      )
+    },
+    rename: (tabId: string, label: string) => {
+      const patched = patchTab(state.unifiedTabsByWorktree, tabId, { customLabel: label })
+      if (patched) {
+        commit({ ...state, ...patched } as AppState)
+      }
+    }
+  }
+}
+
+/** Lets the sync's queued reconcile run to completion before the next host publish. */
+function settle(): Promise<void> {
+  return new Promise((resolve) => setTimeout(resolve, 0))
+}
+
+function chatTabs(state: AppState): Tab[] {
+  return (state.unifiedTabsByWorktree[WORKTREE_ID] ?? []).filter(
+    (tab) => tab.contentType === 'agent-session'
+  )
+}
+
+function labelOf(state: AppState, sessionId: string): string {
+  const tab = chatTabs(state).find((candidate) => candidate.entityId === sessionId)
+  return tab ? resolveUnifiedTabLabel(tab, false, 'Codex Chat') : 'missing'
+}
+
+function titleResolver(
+  titleByProviderSessionId: Record<string, string>
+): (args: AiVaultSessionTitlesArgs) => Promise<AiVaultSessionTitlesResult> {
+  return async (args) => ({
+    titles: args.requests.flatMap((request) => {
+      const title = titleByProviderSessionId[request.sessionId]
+      return title ? [{ agent: request.agent, sessionId: request.sessionId, title }] : []
+    })
+  })
+}
+
+describe('structured Codex chat tab titles', () => {
+  it('adopts the provider session title when the chat tab is created', async () => {
+    const store = makeStore()
+    const stop = startAiVaultTabTitleSync({
+      getState: store.getState,
+      subscribe: store.subscribe,
+      resolveSessionTitles: titleResolver({ 'thread-1': 'Rewrite the parser' })
+    })
+    // Created after the sync is already running, as a real launch is.
+    store.publish(1, [{ sessionId: 'codex-1', providerSessionId: 'thread-1' }])
+
+    await vi.waitFor(() => expect(labelOf(store.getState(), 'codex-1')).toBe('Rewrite the parser'))
+    stop()
+  })
+
+  it('names the chat once the host proves the thread it was launched without', async () => {
+    const store = makeStore()
+    store.publish(1, [{ sessionId: 'codex-1' }])
+    const stop = startAiVaultTabTitleSync({
+      getState: store.getState,
+      subscribe: store.subscribe,
+      resolveSessionTitles: titleResolver({ 'thread-1': 'Rewrite the parser' })
+    })
+    await settle()
+    expect(labelOf(store.getState(), 'codex-1')).toBe('Codex Chat')
+
+    store.publish(2, [{ sessionId: 'codex-1', providerSessionId: 'thread-1' }])
+
+    await vi.waitFor(() => expect(labelOf(store.getState(), 'codex-1')).toBe('Rewrite the parser'))
+    stop()
+  })
+
+  it('picks up a later provider title without ever falling back to the generic label', async () => {
+    const store = makeStore()
+    store.publish(1, [{ sessionId: 'codex-1', providerSessionId: 'thread-1' }])
+    let title = 'Rewrite the parser'
+    let refresh: (() => void) | null = null
+    const delays: number[] = []
+    const stop = startAiVaultTabTitleSync({
+      getState: store.getState,
+      subscribe: store.subscribe,
+      resolveSessionTitles: async () => ({
+        titles: [{ agent: 'codex', sessionId: 'thread-1', title }]
+      }),
+      setTimer: (callback, delay) => {
+        refresh = callback
+        delays.push(delay)
+        return 0
+      },
+      clearTimer: () => {}
+    })
+    await vi.waitFor(() => expect(labelOf(store.getState(), 'codex-1')).toBe(title))
+
+    // The live-session refresh is what carries a renamed thread to the tab.
+    title = 'Ship the parser fix'
+    await vi.waitFor(() => expect(refresh).not.toBeNull())
+    refresh!()
+    await vi.waitFor(() => expect(labelOf(store.getState(), 'codex-1')).toBe(title))
+
+    // A host republish carries no name of its own; the tab must not blink back to the generic one.
+    store.publish(2, [{ sessionId: 'codex-1', providerSessionId: 'thread-1' }])
+    await settle()
+    expect(labelOf(store.getState(), 'codex-1')).toBe(title)
+    expect(store.labelHistory.slice(1)).not.toContain('Codex Chat')
+    // A named chat is on the settled cadence, not the every-20s hunt for a missing name.
+    expect(delays).toEqual([300_000, 300_000])
+    stop()
+  })
+
+  it('keeps a manual rename ahead of a later provider title', async () => {
+    const store = makeStore()
+    store.publish(1, [{ sessionId: 'codex-1', providerSessionId: 'thread-1' }])
+    const tabId = chatTabs(store.getState())[0]!.id
+    store.rename(tabId, 'Parser work')
+    const stop = startAiVaultTabTitleSync({
+      getState: store.getState,
+      subscribe: store.subscribe,
+      resolveSessionTitles: titleResolver({ 'thread-1': 'Rewrite the parser' })
+    })
+
+    await vi.waitFor(() =>
+      expect(chatTabs(store.getState())[0]!.aiVaultTitle?.title).toBe('Rewrite the parser')
+    )
+    store.publish(2, [{ sessionId: 'codex-1', providerSessionId: 'thread-1' }])
+
+    expect(labelOf(store.getState(), 'codex-1')).toBe('Parser work')
+    expect(store.labelHistory).not.toContain('Rewrite the parser')
+    stop()
+  })
+
+  it('restores the provider title and its session identity across a restart', async () => {
+    const store = makeStore()
+    store.publish(1, [{ sessionId: 'codex-1', providerSessionId: 'thread-1' }])
+    const stop = startAiVaultTabTitleSync({
+      getState: store.getState,
+      subscribe: store.subscribe,
+      resolveSessionTitles: titleResolver({ 'thread-1': 'Rewrite the parser' })
+    })
+    await vi.waitFor(() => expect(labelOf(store.getState(), 'codex-1')).toBe('Rewrite the parser'))
+    stop()
+
+    const persisted = buildPersistedUnifiedTabSessionData({
+      activeGroupIdByWorktree: store.getState().activeGroupIdByWorktree,
+      groupsByWorktree: store.getState().groupsByWorktree,
+      layoutByWorktree: store.getState().layoutByWorktree,
+      unifiedTabsByWorktree: store.getState().unifiedTabsByWorktree
+    })
+    const reloaded: WorkspaceSessionState = workspaceSessionStateSchema.parse({
+      ...persisted,
+      activeRepoId: 'repo-1',
+      activeWorktreeId: WORKTREE_ID,
+      activeTabId: null,
+      terminalLayoutsByTabId: {},
+      tabsByWorktree: {}
+    })
+    const hydrated = buildHydratedTabState(reloaded, new Set([WORKTREE_ID]))
+    const restored = hydrated.unifiedTabsByWorktree[WORKTREE_ID]!.find(
+      (tab) => tab.contentType === 'agent-session'
+    )!
+
+    expect(resolveUnifiedTabLabel(restored, false, 'Codex Chat')).toBe('Rewrite the parser')
+    expect(restored.agentSessionProviderSessionId).toBe('thread-1')
+  })
+
+  it('never lets one Codex session name another chat tab', async () => {
+    const store = makeStore()
+    store.publish(1, [
+      { sessionId: 'codex-1', providerSessionId: 'thread-1' },
+      { sessionId: 'codex-2', providerSessionId: 'thread-2' }
+    ])
+    const stop = startAiVaultTabTitleSync({
+      getState: store.getState,
+      subscribe: store.subscribe,
+      resolveSessionTitles: titleResolver({
+        'thread-1': 'Rewrite the parser',
+        'thread-2': 'Fix the flaky suite'
+      })
+    })
+
+    await vi.waitFor(() => {
+      expect(labelOf(store.getState(), 'codex-1')).toBe('Rewrite the parser')
+      expect(labelOf(store.getState(), 'codex-2')).toBe('Fix the flaky suite')
+    })
+    stop()
+
+    // An answer for one thread must not name the other; unknown stays unknown.
+    const partial = makeStore()
+    partial.publish(1, [
+      { sessionId: 'codex-3', providerSessionId: 'thread-3' },
+      { sessionId: 'codex-4', providerSessionId: 'thread-4' }
+    ])
+    const stopPartial = startAiVaultTabTitleSync({
+      getState: partial.getState,
+      subscribe: partial.subscribe,
+      resolveSessionTitles: titleResolver({ 'thread-4': 'Fix the flaky suite' })
+    })
+    await vi.waitFor(() =>
+      expect(labelOf(partial.getState(), 'codex-4')).toBe('Fix the flaky suite')
+    )
+    expect(labelOf(partial.getState(), 'codex-3')).toBe('Codex Chat')
+    stopPartial()
+  })
+})
diff --git a/src/renderer/src/runtime/web-session-tabs-sync.ts b/src/renderer/src/runtime/web-session-tabs-sync.ts
index a213b2dbfe3..653bed6ae0c 100644
--- a/src/renderer/src/runtime/web-session-tabs-sync.ts
+++ b/src/renderer/src/runtime/web-session-tabs-sync.ts
@@ -998,8 +998,17 @@ function buildMirroredAgentTabs(
         worktreeId: snapshot.worktree,
         contentType: 'agent-session',
         agentSessionAgent: tab.agent,
+        // Why: the host owns identity, the client owns the name. Dropping either on a republish
+        // renamed the tab back to the generic label and lost the user's own rename with it.
+        ...((tab.providerSessionId ?? existing?.agentSessionProviderSessionId)
+          ? {
+              agentSessionProviderSessionId:
+                tab.providerSessionId ?? existing?.agentSessionProviderSessionId
+            }
+          : {}),
         label: tab.title.trim() || 'Codex Chat',
-        customLabel: null,
+        ...(existing?.aiVaultTitle ? { aiVaultTitle: existing.aiVaultTitle } : {}),
+        customLabel: existing?.customLabel ?? null,
         color: tab.color !== undefined ? tab.color : (existing?.color ?? null),
         sortOrder: sortOffset + index,
         createdAt: existing?.createdAt ?? now + sortOffset + index,
@@ -2670,6 +2679,7 @@ function tabEqual(a: Tab, b: Tab): boolean {
     a.executionHostId === b.executionHostId &&
     a.contentType === b.contentType &&
     a.agentSessionAgent === b.agentSessionAgent &&
+    a.agentSessionProviderSessionId === b.agentSessionProviderSessionId &&
     a.label === b.label &&
     // Why: the generated label is the visible tab title; ignoring it let the
     // equality bail keep a unified tab that disagreed with its terminal tab.
diff --git a/src/renderer/src/store/slices/agent-session-tab-ai-vault-title.ts b/src/renderer/src/store/slices/agent-session-tab-ai-vault-title.ts
new file mode 100644
index 00000000000..fb2d0631ba1
--- /dev/null
+++ b/src/renderer/src/store/slices/agent-session-tab-ai-vault-title.ts
@@ -0,0 +1,37 @@
+import type { AiVaultSessionTitle } from '../../../../shared/ai-vault-session-title'
+import type { Tab } from '../../../../shared/tab-types'
+
+function sameTitle(
+  left: AiVaultSessionTitle | null | undefined,
+  right: AiVaultSessionTitle | null | undefined
+): boolean {
+  return (
+    left?.agent === right?.agent &&
+    left?.sessionId === right?.sessionId &&
+    left?.title === right?.title
+  )
+}
+
+/**
+ * Names a structured chat tab from the AI Vault pipeline. Structured chats have no terminal tab to
+ * carry the name, so the unified row is the only record of it.
+ *
+ * Returns null when nothing changed, so an unchanged provider name never re-renders the tab strip.
+ */
+export function applyAgentSessionAiVaultTitle(
+  unifiedTabsByWorktree: Record<string, Tab[]>,
+  tabId: string,
+  aiVaultTitle: AiVaultSessionTitle | null
+): Record<string, Tab[]> | null {
+  for (const [worktreeId, tabs] of Object.entries(unifiedTabsByWorktree)) {
+    const current = tabs.find((tab) => tab.contentType === 'agent-session' && tab.id === tabId)
+    if (!current || sameTitle(current.aiVaultTitle, aiVaultTitle)) {
+      continue
+    }
+    return {
+      ...unifiedTabsByWorktree,
+      [worktreeId]: tabs.map((tab) => (tab.id === tabId ? { ...tab, aiVaultTitle } : tab))
+    }
+  }
+  return null
+}
diff --git a/src/renderer/src/store/terminals/terminal-tab-presentation.ts b/src/renderer/src/store/terminals/terminal-tab-presentation.ts
index 7e1d2f64442..582376b0bf3 100644
--- a/src/renderer/src/store/terminals/terminal-tab-presentation.ts
+++ b/src/renderer/src/store/terminals/terminal-tab-presentation.ts
@@ -5,6 +5,7 @@ import {
   applyGeneratedTabTitleUpdates,
   applyTerminalTabTitleUpdates
 } from '../slices/terminal-tab-title-batch'
+import { applyAgentSessionAiVaultTitle } from '../slices/agent-session-tab-ai-vault-title'
 import {
   adoptTerminalTabOwnerMetadataOnlyBuckets,
   getTerminalTabOwnerWorktreeId
@@ -52,7 +53,16 @@ export function createTerminalTabPresentationActions(
       set((s) => {
         const ownerWorktreeId = getTerminalTabOwnerWorktreeId(s.tabsByWorktree, tabId)
         if (!ownerWorktreeId) {
-          return s
+          const unifiedTabsByWorktree = applyAgentSessionAiVaultTitle(
+            s.unifiedTabsByWorktree,
+            tabId,
+            aiVaultTitle
+          )
+          if (!unifiedTabsByWorktree) {
+            return s
+          }
+          scheduleRuntimeGraphSync()
+          return { unifiedTabsByWorktree }
         }
         const tabs = s.tabsByWorktree[ownerWorktreeId] ?? []
         const current = tabs.find((tab) => tab.id === tabId)
diff --git a/src/shared/runtime-mobile-session-tab-contracts.ts b/src/shared/runtime-mobile-session-tab-contracts.ts
index 40f60230218..e9f549b478f 100644
--- a/src/shared/runtime-mobile-session-tab-contracts.ts
+++ b/src/shared/runtime-mobile-session-tab-contracts.ts
@@ -92,6 +92,9 @@ export type RuntimeMobileSessionAgentTab = {
   title: string
   sessionId: string
   agent: 'codex'
+  /** Provider conversation the session is bound to (Codex thread id). Absent until the provider
+   *  proves one — absence is unknown identity, never a title. */
+  providerSessionId?: string
   color?: string | null
   isPinned?: boolean
   isActive: boolean
diff --git a/src/shared/tab-types.ts b/src/shared/tab-types.ts
index 5f2b74d7127..12fd27b2e35 100644
--- a/src/shared/tab-types.ts
+++ b/src/shared/tab-types.ts
@@ -70,6 +70,9 @@ export type Tab = {
   isPinned?: boolean // pinned tabs survive "close others"
   /** Provider backing a structured agent-session tab. */
   agentSessionAgent?: AgentType
+  /** Provider conversation id behind a structured agent-session tab, so the AI Vault title
+   *  pipeline can name it exactly as it names a terminal-backed session. */
+  agentSessionProviderSessionId?: string
   /** Structured session adopted from this terminal's Codex TUI. */
   structuredSessionId?: string
   /** Why: per-tab rendering mode for coding-agent terminals. `'chat'` shows the
diff --git a/src/shared/workspace-session-schema.ts b/src/shared/workspace-session-schema.ts
index 2ed368baedf..4b8d77cb206 100644
--- a/src/shared/workspace-session-schema.ts
+++ b/src/shared/workspace-session-schema.ts
@@ -128,6 +128,9 @@ const tabSchema = z.object({
   // Why: a structured terminal tab must recover its durable host session after
   // restart; omitting this additive field silently routes it back through PTY.
   structuredSessionId: z.string().min(1).optional().catch(undefined),
+  // Why: the provider conversation id is what the AI Vault title pipeline keys on; without it a
+  // restored chat tab cannot refresh its own name until the host republishes.
+  agentSessionProviderSessionId: z.string().min(1).optional().catch(undefined),
   label: z.string(),
   generatedLabel: z.string().nullable().optional(),
   aiVaultTitle: z