diff --git a/internal/cloud/access-control.test.ts b/internal/cloud/access-control.test.ts
index 9f3719ba..fcf8b519 100644
--- a/internal/cloud/access-control.test.ts
+++ b/internal/cloud/access-control.test.ts
@@ -288,6 +288,76 @@ test("cloud api access control grants visible device pods and requires device-po
   }
 });
 
+test("cloud api stores and restores Code Agent conversations by authenticated account", async () => {
+  const server = createCloudApiServer({
+    env: {
+      HWLAB_ACCESS_CONTROL_REQUIRED: "1",
+      HWLAB_BOOTSTRAP_ADMIN_USERNAME: "admin",
+      HWLAB_BOOTSTRAP_ADMIN_PASSWORD: "admin-pass"
+    },
+    now: () => "2026-05-31T07:30:00.000Z"
+  });
+  await new Promise((resolve) => server.listen(0, "127.0.0.1", resolve));
+
+  try {
+    const { port } = server.address();
+    const adminLogin = await postJson(port, "/auth/login", { username: "admin", password: "admin-pass" });
+    const adminCookie = adminLogin.cookie;
+    const aliceCreate = await postJson(port, "/v1/admin/users", { username: "alice", password: "alice-pass" }, adminCookie);
+    const bobCreate = await postJson(port, "/v1/admin/users", { username: "bob", password: "bob-pass" }, adminCookie);
+    assert.equal(aliceCreate.status, 201);
+    assert.equal(bobCreate.status, 201);
+
+    const aliceLogin = await postJson(port, "/auth/login", { username: "alice", password: "alice-pass" });
+    const bobLogin = await postJson(port, "/auth/login", { username: "bob", password: "bob-pass" });
+
+    const stored = await putJson(port, "/v1/agent/conversations/cnv_account_sync", {
+      projectId: "prj_device_pod_workbench",
+      sessionId: "ses_account_sync",
+      threadId: "thread-account-sync",
+      lastTraceId: "trc_account_sync",
+      sessionStatus: "idle",
+      messages: [
+        { id: "msg_user", role: "user", title: "用户", text: "在吗", status: "sent", conversationId: "cnv_account_sync", sessionId: "ses_account_sync", threadId: "thread-account-sync" },
+        { id: "msg_agent", role: "agent", title: "Agent", text: "在", status: "completed", traceId: "trc_account_sync", conversationId: "cnv_account_sync", sessionId: "ses_account_sync", threadId: "thread-account-sync" }
+      ]
+    }, aliceLogin.cookie);
+    assert.equal(stored.status, 200);
+    assert.equal(stored.body.conversation.conversationId, "cnv_account_sync");
+    assert.equal(stored.body.conversation.sessionId, "ses_account_sync");
+    assert.equal(stored.body.conversation.threadId, "thread-account-sync");
+    assert.equal(stored.body.conversation.status, "idle");
+    assert.equal(stored.body.conversation.messages.length, 2);
+
+    const aliceList = await getJson(port, "/v1/agent/conversations?projectId=prj_device_pod_workbench", aliceLogin.cookie);
+    assert.equal(aliceList.status, 200);
+    assert.equal(aliceList.body.count, 1);
+    assert.equal(aliceList.body.defaultConversation.conversationId, "cnv_account_sync");
+    assert.equal(aliceList.body.defaultConversation.messages[1].text, "在");
+    assert.equal(aliceList.body.defaultConversation.valuesRedacted, true);
+
+    const bobList = await getJson(port, "/v1/agent/conversations?projectId=prj_device_pod_workbench", bobLogin.cookie);
+    assert.equal(bobList.status, 200);
+    assert.deepEqual(bobList.body.conversations, []);
+
+    const bobDirect = await getJson(port, "/v1/agent/conversations/cnv_account_sync", bobLogin.cookie);
+    assert.equal(bobDirect.status, 404);
+    assert.equal(bobDirect.body.error.code, "agent_conversation_not_found");
+
+    const logout = await postJson(port, "/auth/logout", {}, aliceLogin.cookie);
+    assert.equal(logout.status, 200);
+    const relogin = await postJson(port, "/auth/login", { username: "alice", password: "alice-pass" });
+    const restored = await getJson(port, "/v1/agent/conversations/cnv_account_sync", relogin.cookie);
+    assert.equal(restored.status, 200);
+    assert.equal(restored.body.conversation.threadId, "thread-account-sync");
+    assert.equal(restored.body.conversation.messages[0].text, "在吗");
+  } finally {
+    await new Promise((resolve, reject) => {
+      server.close((error) => (error ? reject(error) : resolve()));
+    });
+  }
+});
+
 test("cloud api protects device-pod routes when access control is required", async () => {
   const server = createCloudApiServer({
     env: { HWLAB_ACCESS_CONTROL_REQUIRED: "1" },
@@ -988,6 +1058,23 @@ function devicePodInternalHeaders(extra = {}) {
   return { ...extra, "x-hwlab-internal-service": "hwlab-device-pod", "x-hwlab-internal-token": INTERNAL_TOKEN };
 }
 
+async function putJson(port, path, body, cookie = null, extraHeaders = {}) {
+  const response = await fetch(`http://127.0.0.1:${port}${path}`, {
+    method: "PUT",
+    headers: {
+      "content-type": "application/json",
+      ...(cookie ? { cookie } : {}),
+      ...extraHeaders
+    },
+    body: JSON.stringify(body)
+  });
+  return {
+    status: response.status,
+    body: await response.json(),
+    cookie: response.headers.get("set-cookie")
+  };
+}
+
 async function getJson(port, path, cookie = null) {
   const response = await fetch(`http://127.0.0.1:${port}${path}`, {
     headers: cookie ? { cookie } : {}
diff --git a/internal/cloud/access-control.ts b/internal/cloud/access-control.ts
index 43e1a17a..24549dca 100644
--- a/internal/cloud/access-control.ts
+++ b/internal/cloud/access-control.ts
@@ -523,6 +523,77 @@ class AccessController {
     }) ?? null;
   }
 
+  async listAgentConversations(request, response, url) {
+    await this.ensureBootstrap();
+    const auth = await this.authenticate(request, { required: true });
+    if (!auth.ok) return sendJson(response, auth.status, auth);
+    const projectId = textOr(url.searchParams.get("projectId"), "");
+    const limit = boundedListLimit(url.searchParams.get("limit"));
+    const sessions = await this.store.listAgentSessionsForUser?.({
+      ownerUserId: auth.actor.id,
+      actorRole: auth.actor.role,
+      ownerScoped: true,
+      projectId,
+      limit,
+      now: this.now()
+    }) ?? [];
+    const conversations = conversationsFromAgentSessions(sessions);
+    return sendJson(response, 200, {
+      ok: true,
+      status: "succeeded",
+      contractVersion: "agent-conversations-v1",
+      actor: publicActor(auth.actor),
+      projectId: projectId || null,
+      conversations,
+      defaultConversation: conversations[0] ?? null,
+      count: conversations.length
+    });
+  }
+
+  async getAgentConversation(request, response, conversationId) {
+    await this.ensureBootstrap();
+    const auth = await this.authenticate(request, { required: true });
+    if (!auth.ok) return sendJson(response, auth.status, auth);
+    if (!safeConversationIdLocal(conversationId)) {
+      return sendJson(response, 400, errorPayload("invalid_conversation_id", "conversationId must start with cnv_", 400));
+    }
+    const sessions = await this.store.listAgentSessionsForUser?.({
+      ownerUserId: auth.actor.id,
+      actorRole: auth.actor.role,
+      ownerScoped: true,
+      conversationId,
+      limit: 20,
+      now: this.now()
+    }) ?? [];
+    const conversation = conversationsFromAgentSessions(sessions).find((item) => item.conversationId === conversationId) ?? null;
+    if (!conversation) return sendJson(response, 404, errorPayload("agent_conversation_not_found", "Agent conversation is not visible to the current actor", 404));
+    return sendJson(response, 200, { ok: true, status: "found", contractVersion: "agent-conversations-v1", actor: publicActor(auth.actor), conversation });
+  }
+
+  async updateAgentConversation(request, response, conversationId) {
+    await this.ensureBootstrap();
+    const auth = await this.authenticate(request, { required: true });
+    if (!auth.ok) return sendJson(response, auth.status, auth);
+    if (!safeConversationIdLocal(conversationId)) {
+      return sendJson(response, 400, errorPayload("invalid_conversation_id", "conversationId must start with cnv_", 400));
+    }
+    const body = await jsonBody(request);
+    const sessionId = safeAgentSessionId(body.sessionId) || safeAgentSessionId(body.session?.sessionId) || `ses_${conversationId.slice(4)}`;
+    const session = await this.recordAgentSessionOwner({
+      ownerUserId: auth.actor.id,
+      sessionId,
+      projectId: textOr(body.projectId, "prj_device_pod_workbench"),
+      agentId: textOr(body.agentId, "hwlab-code-agent"),
+      status: textOr(body.status ?? body.sessionStatus, "active"),
+      conversationId,
+      threadId: textOr(body.threadId, null),
+      traceId: textOr(body.lastTraceId ?? body.traceId, null),
+      session: normalizeConversationSnapshot(body, auth.actor)
+    });
+    const conversation = conversationsFromAgentSessions(session ? [session] : []).find((item) => item.conversationId === conversationId) ?? null;
+    return sendJson(response, 200, { ok: true, status: "stored", contractVersion: "agent-conversations-v1", conversation });
+  }
+
   async requireGrantTargets({ devicePodId, userId }) {
     const pod = await this.store.getDevicePod(devicePodId);
     if (!pod || pod.status !== "active") {
@@ -1097,6 +1168,19 @@ class MemoryAccessStore {
     return session;
   }
   async getAgentSession(id) { return this.agentSessions.get(id) ?? null; }
+  async listAgentSessionsForUser(input = {}) {
+    const ownerUserId = textOr(input.ownerUserId, "");
+    const role = textOr(input.actorRole, "user");
+    const projectId = textOr(input.projectId, "");
+    const conversationId = textOr(input.conversationId, "");
+    const limit = boundedListLimit(input.limit);
+    return [...this.agentSessions.values()]
+      .filter((session) => input.ownerScoped === true || role !== "admin" ? session.ownerUserId === ownerUserId : true)
+      .filter((session) => !projectId || session.projectId === projectId)
+      .filter((session) => !conversationId || session.conversationId === conversationId)
+      .sort((a, b) => String(b.updatedAt ?? "").localeCompare(String(a.updatedAt ?? "")))
+      .slice(0, limit);
+  }
 }
 
 class PostgresAccessStore extends MemoryAccessStore {
@@ -1174,10 +1258,38 @@ class PostgresAccessStore extends MemoryAccessStore {
   async recordAgentSessionOwner(input) {
     await this.ensureSchema();
     const now = input.now ?? this.now();
-    const session = normalizeAgentSessionOwnerRecord(input, null, now);
+    const existing = input.sessionId ? await this.getAgentSession(input.sessionId) : null;
+    const session = normalizeAgentSessionOwnerRecord(input, existing, now);
     const result = await this.query("INSERT INTO agent_sessions (id, project_id, agent_id, status, started_at, ended_at, owner_user_id, conversation_id, thread_id, last_trace_id, session_json, updated_at) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12) ON CONFLICT (id) DO UPDATE SET project_id = COALESCE(EXCLUDED.project_id, agent_sessions.project_id), agent_id = EXCLUDED.agent_id, status = EXCLUDED.status, ended_at = EXCLUDED.ended_at, owner_user_id = EXCLUDED.owner_user_id, conversation_id = COALESCE(EXCLUDED.conversation_id, agent_sessions.conversation_id), thread_id = COALESCE(EXCLUDED.thread_id, agent_sessions.thread_id), last_trace_id = COALESCE(EXCLUDED.last_trace_id, agent_sessions.last_trace_id), session_json = EXCLUDED.session_json, updated_at = EXCLUDED.updated_at RETURNING id, project_id, agent_id, status, started_at, ended_at, owner_user_id, conversation_id, thread_id, last_trace_id, session_json, updated_at", [session.id, session.projectId, session.agentId, session.status, session.startedAt, session.endedAt, session.ownerUserId, session.conversationId, session.threadId, session.lastTraceId, stableJson(session.session ?? {}), session.updatedAt]);
     return pgAgentSession(result.rows?.[0]);
   }
+  async getAgentSession(id) { await this.ensureSchema(); const result = await this.query("SELECT id, project_id, agent_id, status, started_at, ended_at, owner_user_id, conversation_id, thread_id, last_trace_id, session_json, updated_at FROM agent_sessions WHERE id = $1 LIMIT 1", [id]); return pgAgentSession(result.rows?.[0]); }
+  async listAgentSessionsForUser(input = {}) {
+    await this.ensureSchema();
+    const role = textOr(input.actorRole, "user");
+    const ownerUserId = textOr(input.ownerUserId, "");
+    const projectId = textOr(input.projectId, "");
+    const conversationId = textOr(input.conversationId, "");
+    const limit = boundedListLimit(input.limit);
+    const clauses = [];
+    const params = [];
+    if (input.ownerScoped === true || role !== "admin") {
+      params.push(ownerUserId);
+      clauses.push(`owner_user_id = $${params.length}`);
+    }
+    if (projectId) {
+      params.push(projectId);
+      clauses.push(`project_id = $${params.length}`);
+    }
+    if (conversationId) {
+      params.push(conversationId);
+      clauses.push(`conversation_id = $${params.length}`);
+    }
+    params.push(limit);
+    const sql = `SELECT id, project_id, agent_id, status, started_at, ended_at, owner_user_id, conversation_id, thread_id, last_trace_id, session_json, updated_at FROM agent_sessions ${clauses.length ? `WHERE ${clauses.join(" AND ")}` : ""} ORDER BY updated_at DESC NULLS LAST LIMIT $${params.length}`;
+    const result = await this.query(sql, params);
+    return result.rows.map(pgAgentSession);
+  }
 }
 
 function parseDevicePodPath(pathname) {
@@ -1295,6 +1407,92 @@ function formatEventLine(event) { return [event.ts?.slice(11, 19) ?? "00:00:00",
 function normalizeJob(input) { return { id: input.id, devicePodId: input.devicePodId, ownerUserId: input.ownerUserId, status: input.status, intent: input.intent, args: normalizeObject(input.args), reason: input.reason ?? "", traceId: input.traceId, operationId: input.operationId, output: normalizeObject(input.output), blocker: input.blocker ?? null, createdAt: input.now, updatedAt: input.now, completedAt: input.completedAt ?? null }; }
 function normalizeAgentSessionOwnerRecord(input, existing, now) { return { id: input.sessionId, projectId: input.projectId ?? existing?.projectId ?? "prj_v02_code_agent", agentId: input.agentId ?? existing?.agentId ?? "hwlab-code-agent", status: input.status ?? existing?.status ?? "active", startedAt: existing?.startedAt ?? input.startedAt ?? now, endedAt: input.endedAt ?? existing?.endedAt ?? null, ownerUserId: input.ownerUserId, conversationId: input.conversationId ?? existing?.conversationId ?? null, threadId: input.threadId ?? existing?.threadId ?? null, lastTraceId: input.traceId ?? input.lastTraceId ?? existing?.lastTraceId ?? null, session: normalizeObject(input.session ?? existing?.session), updatedAt: now }; }
 function agentSessionIdForRecord(sessionId, traceId) { const sessionText = textOr(sessionId, ""); if (/^ses_[A-Za-z0-9_.:-]+$/u.test(sessionText)) return sessionText; const traceText = textOr(traceId, ""); return /^trc_[A-Za-z0-9_.:-]+$/u.test(traceText) ? `ses_pending_${traceText.slice(4)}` : null; }
+function safeConversationIdLocal(value) { return /^cnv_[A-Za-z0-9_.:-]+$/u.test(textOr(value, "")); }
+function boundedListLimit(value) { const parsed = Number.parseInt(String(value ?? ""), 10); return Math.min(Math.max(Number.isInteger(parsed) && parsed > 0 ? parsed : 20, 1), 100); }
+function normalizeConversationSnapshot(body = {}, actor = null) {
+  const snapshot = normalizeObject(body.snapshot ?? body);
+  const messagesSource = Array.isArray(body.messages) ? body.messages : snapshot.messages;
+  const chatMessagesSource = Array.isArray(body.chatMessages) ? body.chatMessages : snapshot.chatMessages;
+  return {
+    ...snapshot,
+    messages: Array.isArray(messagesSource) ? messagesSource.slice(-50).map(redactConversationMessage).filter(Boolean) : [],
+    chatMessages: Array.isArray(chatMessagesSource) ? chatMessagesSource.slice(-50).map(redactConversationMessage).filter(Boolean) : undefined,
+    actor: actor ? publicActor(actor) : undefined,
+    secretMaterialStored: false,
+    valuesRedacted: true
+  };
+}
+function redactConversationMessage(message) {
+  if (!message || typeof message !== "object") return null;
+  const runnerTrace = message.runnerTrace && typeof message.runnerTrace === "object" ? message.runnerTrace : null;
+  return pruneEmpty({
+    id: textOr(message.id, ""),
+    role: textOr(message.role, ""),
+    title: textOr(message.title, ""),
+    text: boundedText(message.text, 12000),
+    status: textOr(message.status, ""),
+    traceId: textOr(message.traceId, ""),
+    conversationId: textOr(message.conversationId, ""),
+    sessionId: textOr(message.sessionId, ""),
+    threadId: textOr(message.threadId, ""),
+    retryOf: textOr(message.retryOf, ""),
+    createdAt: textOr(message.createdAt, ""),
+    updatedAt: textOr(message.updatedAt, ""),
+    runnerTrace: runnerTrace ? pruneEmpty({
+      traceId: runnerTrace.traceId,
+      status: runnerTrace.status,
+      sessionId: runnerTrace.sessionId,
+      threadId: runnerTrace.threadId,
+      eventCount: runnerTrace.eventCount,
+      eventsCompacted: runnerTrace.eventsCompacted === true,
+      fullTraceLoaded: runnerTrace.fullTraceLoaded === true,
+      lastEvent: runnerTrace.lastEvent
+    }) : undefined
+  });
+}
+function conversationsFromAgentSessions(sessions = []) {
+  const byConversation = new Map();
+  for (const session of sessions) {
+    const conversationId = textOr(session.conversationId, "");
+    if (!conversationId) continue;
+    const previous = byConversation.get(conversationId);
+    if (previous && String(previous.updatedAt ?? "") >= String(session.updatedAt ?? "")) continue;
+    byConversation.set(conversationId, publicAgentConversation(session));
+  }
+  return [...byConversation.values()].sort((a, b) => String(b.updatedAt ?? "").localeCompare(String(a.updatedAt ?? "")));
+}
+function publicAgentConversation(session) {
+  const snapshot = normalizeObject(session.session);
+  const messages = Array.isArray(snapshot.messages) ? snapshot.messages : Array.isArray(snapshot.chatMessages) ? snapshot.chatMessages : [];
+  return {
+    conversationId: session.conversationId,
+    sessionId: session.id,
+    threadId: session.threadId,
+    status: session.status,
+    projectId: session.projectId,
+    agentId: session.agentId,
+    ownerUserId: session.ownerUserId,
+    lastTraceId: session.lastTraceId,
+    updatedAt: session.updatedAt,
+    startedAt: session.startedAt,
+    endedAt: session.endedAt,
+    session: pruneEmpty({ sessionId: session.id, threadId: session.threadId, status: session.status }),
+    messages,
+    snapshot: pruneEmpty({
+      sessionStatus: snapshot.sessionStatus,
+      source: snapshot.source,
+      updatedAt: snapshot.updatedAt,
+      valuesRedacted: snapshot.valuesRedacted !== false
+    }),
+    valuesRedacted: true
+  };
+}
+function boundedText(value, maxBytes) {
+  const text = String(value ?? "");
+  const buffer = Buffer.from(text, "utf8");
+  return buffer.length > maxBytes ? buffer.subarray(0, maxBytes).toString("utf8") : text;
+}
+function pruneEmpty(value) { return Object.fromEntries(Object.entries(value).filter(([, item]) => item !== undefined && item !== "" && item !== null)); }
 function sessionTokenFromRequest(request) { const auth = getHeader(request, "authorization"); if (/^Bearer\s+/iu.test(String(auth ?? ""))) return String(auth).replace(/^Bearer\s+/iu, "").trim(); const header = textOr(getHeader(request, "x-hwlab-session-token"), ""); if (header) return header; const cookie = parseCookie(getHeader(request, "cookie")); return cookie[SESSION_COOKIE] ?? ""; }
 function parseCookie(value) { return Object.fromEntries(String(value ?? "").split(";").map((part) => part.trim()).filter(Boolean).map((part) => { const index = part.indexOf("="); return index > 0 ? [part.slice(0, index), decodeURIComponent(part.slice(index + 1))] : [part, ""]; })); }
 function setSessionCookie(response, token, maxAge) { response.setHeader("set-cookie", `${SESSION_COOKIE}=${encodeURIComponent(token)}; Path=/; HttpOnly; SameSite=Lax; Max-Age=${maxAge}`); }
diff --git a/internal/cloud/code-agent-chat.ts b/internal/cloud/code-agent-chat.ts
index a14a7ace..9ade2ffc 100644
--- a/internal/cloud/code-agent-chat.ts
+++ b/internal/cloud/code-agent-chat.ts
@@ -125,6 +125,7 @@ export async function handleCodeAgentChat(params = {}, options = {}) {
         message,
         conversationId,
         sessionId: requestedSessionId,
+        threadId: params.threadId,
         traceId,
         env: options.env ?? process.env,
         now: options.now,
@@ -839,13 +840,14 @@ function notRequestedSkills() {
   };
 }
 
-async function callCodexStdioRunner({ message, conversationId, sessionId, traceId, env, now, workspace, timeoutMs, hardTimeoutMs, model, codexStdioManager, skillsDirs, skillsDirsExact, traceRecorder, conversationFacts, externalNetworkIntent = null }) {
+async function callCodexStdioRunner({ message, conversationId, sessionId, threadId, traceId, env, now, workspace, timeoutMs, hardTimeoutMs, model, codexStdioManager, skillsDirs, skillsDirsExact, traceRecorder, conversationFacts, externalNetworkIntent = null }) {
   const manager = resolveCodexStdioSessionManager({ codexStdioManager });
   try {
     return await manager.chat({
       message,
       conversationId,
       sessionId,
+      threadId,
       traceId,
       env,
       now,
diff --git a/internal/cloud/code-agent-session-registry.test.ts b/internal/cloud/code-agent-session-registry.test.ts
index d2bc5c1a..8621ee26 100644
--- a/internal/cloud/code-agent-session-registry.test.ts
+++ b/internal/cloud/code-agent-session-registry.test.ts
@@ -1230,6 +1230,134 @@ function createPartialAssistantNoTurnCompletedClient({ calls, text = "partial as
   };
 }
 
+test("Codex stdio resumes an idle-expired thread instead of returning no-event timeout", async () => {
+  const calls = [];
+  const fakeCodex = await createFakeCodexCommand();
+  const codexHome = await prepareFakeCodexHome();
+  const manager = createCodexStdioSessionManager({
+    idleTimeoutMs: 10,
+    idFactory: () => "ses_stdio_idle_resume",
+    createRpcClient: async () => createFakeAppServerClient({
+      calls,
+      responses: ["first response", "resumed response"]
+    })
+  });
+  const env = {
+    PATH: process.env.PATH,
+    OPENAI_API_KEY: "test-openai-key-material",
+    CODEX_HOME: codexHome,
+    HWLAB_CODE_AGENT_PROVIDER: "codex-stdio",
+    HWLAB_CODE_AGENT_MODEL: "gpt-test",
+    HWLAB_CODE_AGENT_CODEX_COMMAND: fakeCodex.command,
+    HWLAB_CODE_AGENT_CODEX_STDIO_ENABLED: "1",
+    HWLAB_CODE_AGENT_CODEX_STDIO_SUPERVISOR: "repo-owned",
+    HWLAB_CODE_AGENT_CODEX_WORKSPACE: process.cwd(),
+    HWLAB_CODE_AGENT_CODEX_SANDBOX: "danger-full-access",
+    HWLAB_CODE_AGENT_OPENAI_BASE_URL: "http://127.0.0.1:49280/responses"
+  };
+
+  try {
+    const first = await handleCodeAgentChat(
+      {
+        conversationId: "cnv_stdio_idle_resume",
+        traceId: "trc_stdio_idle_resume_first",
+        message: "第一轮"
+      },
+      {
+        now: () => "2026-05-31T00:00:00.000Z",
+        env,
+        codexStdioManager: manager
+      }
+    );
+    validateCodeAgentChatSchema(first);
+    assert.equal(first.status, "completed");
+    assert.equal(first.session.threadId, "thread_stdio_ready");
+
+    const second = await handleCodeAgentChat(
+      {
+        conversationId: "cnv_stdio_idle_resume",
+        sessionId: first.sessionId,
+        threadId: first.session.threadId,
+        traceId: "trc_stdio_idle_resume_second",
+        message: "一小时后继续"
+      },
+      {
+        now: () => "2026-05-31T01:00:00.000Z",
+        env,
+        codexStdioManager: manager
+      }
+    );
+
+    validateCodeAgentChatSchema(second);
+    assert.equal(second.status, "completed");
+    assert.equal(second.error, undefined);
+    assert.equal(second.session.sessionId, "ses_stdio_idle_resume");
+    assert.equal(second.session.threadId, "thread_stdio_ready");
+    assert.equal(second.session.turn, 2);
+    assert.equal(second.sessionReuse.reused, true);
+    assert.deepEqual(calls.filter((call) => call.method === "thread/start").map((call) => call.args.serviceName), ["hwlab-cloud-api"]);
+    assert.deepEqual(calls.filter((call) => call.method === "thread/resume").map((call) => call.args.threadId), ["thread_stdio_ready"]);
+    assert.equal(calls.filter((call) => call.method === "turn/start").length, 2);
+  } finally {
+    await rm(fakeCodex.root, { recursive: true, force: true });
+    await rm(codexHome, { recursive: true, force: true });
+  }
+});
+
+test("Codex stdio uses a persisted thread id after manager restart", async () => {
+  const calls = [];
+  const fakeCodex = await createFakeCodexCommand();
+  const codexHome = await prepareFakeCodexHome();
+  const manager = createCodexStdioSessionManager({
+    idFactory: () => "ses_should_not_replace_persisted",
+    createRpcClient: async () => createFakeAppServerClient({
+      calls,
+      responses: ["resumed after restart"]
+    })
+  });
+  const env = {
+    PATH: process.env.PATH,
+    OPENAI_API_KEY: "test-openai-key-material",
+    CODEX_HOME: codexHome,
+    HWLAB_CODE_AGENT_PROVIDER: "codex-stdio",
+    HWLAB_CODE_AGENT_MODEL: "gpt-test",
+    HWLAB_CODE_AGENT_CODEX_COMMAND: fakeCodex.command,
+    HWLAB_CODE_AGENT_CODEX_STDIO_ENABLED: "1",
+    HWLAB_CODE_AGENT_CODEX_STDIO_SUPERVISOR: "repo-owned",
+    HWLAB_CODE_AGENT_CODEX_WORKSPACE: process.cwd(),
+    HWLAB_CODE_AGENT_CODEX_SANDBOX: "danger-full-access",
+    HWLAB_CODE_AGENT_OPENAI_BASE_URL: "http://127.0.0.1:49280/responses"
+  };
+
+  try {
+    const payload = await handleCodeAgentChat(
+      {
+        conversationId: "cnv_stdio_restart_resume",
+        sessionId: "ses_stdio_restart_resume",
+        threadId: "thread_persisted_account",
+        traceId: "trc_stdio_restart_resume",
+        message: "恢复上次账号会话"
+      },
+      {
+        now: () => "2026-05-31T01:05:00.000Z",
+        env,
+        codexStdioManager: manager
+      }
+    );
+
+    validateCodeAgentChatSchema(payload);
+    assert.equal(payload.status, "completed");
+    assert.equal(payload.session.sessionId, "ses_stdio_restart_resume");
+    assert.equal(payload.session.threadId, "thread_persisted_account");
+    assert.deepEqual(calls.filter((call) => call.method === "thread/start"), []);
+    assert.deepEqual(calls.filter((call) => call.method === "thread/resume").map((call) => call.args.threadId), ["thread_persisted_account"]);
+    assert.equal(calls.filter((call) => call.method === "turn/start")[0].args.threadId, "thread_persisted_account");
+  } finally {
+    await rm(fakeCodex.root, { recursive: true, force: true });
+    await rm(codexHome, { recursive: true, force: true });
+  }
+});
+
 test("Codex stdio manager reports concrete blockers without falling back to readonly", async () => {
   const manager = createCodexStdioSessionManager({
     idFactory: () => "ses_stdio_blocked"
diff --git a/internal/cloud/codex-stdio-session.ts b/internal/cloud/codex-stdio-session.ts
index 38914b26..626d9838 100644
--- a/internal/cloud/codex-stdio-session.ts
+++ b/internal/cloud/codex-stdio-session.ts
@@ -488,6 +488,7 @@ export function createCodexStdioSessionManager(options = {}) {
     const acquire = await acquireSession({
       conversationId,
       requestedSessionId: params.sessionId,
+      threadId: params.threadId,
       traceId,
       workspace,
       sandbox,
@@ -1109,6 +1110,7 @@ export function createCodexStdioSessionManager(options = {}) {
     const timestampMs = Date.parse(timestamp);
     const conversationId = requiredId(params.conversationId, "cnv");
     const requestedSessionId = optionalId(params.requestedSessionId);
+    const requestedThreadId = optionalId(params.threadId);
     const mappedSessionId = conversations.get(conversationId) ?? null;
 
     if (mappedSessionId && requestedSessionId && mappedSessionId !== requestedSessionId) {
@@ -1127,17 +1129,28 @@ export function createCodexStdioSessionManager(options = {}) {
     let reused = Boolean(session);
 
     if (session && sessionExpired(session, timestampMs)) {
-      session.status = "expired";
-      session.updatedAt = timestamp;
-      session.currentTraceId = null;
-      session.lastTraceId = optionalId(params.traceId) ?? session.lastTraceId;
-      return blockedAcquire({
-        code: "session_expired",
-        summary: `Codex stdio session ${effectiveSessionId} expired after ${session.idleTimeoutMs}ms idle timeout.`,
-        session,
-        timestamp,
-        traceId: params.traceId
-      });
+      const resumeThreadId = requestedThreadId ?? optionalId(session.threadId);
+      if (["idle", "expired"].includes(session.status) && resumeThreadId) {
+        session.status = "idle";
+        session.threadId = resumeThreadId;
+        session.updatedAt = timestamp;
+        session.expiresAt = plusMs(timestampMs, idleTimeoutMs);
+        session.currentTraceId = null;
+        session.lastTraceId = optionalId(params.traceId) ?? session.lastTraceId;
+        session.statusReason = "idle_timeout_resume";
+      } else {
+        session.status = "expired";
+        session.updatedAt = timestamp;
+        session.currentTraceId = null;
+        session.lastTraceId = optionalId(params.traceId) ?? session.lastTraceId;
+        return blockedAcquire({
+          code: "session_expired",
+          summary: `Codex stdio session ${effectiveSessionId} expired after ${session.idleTimeoutMs}ms idle timeout.`,
+          session,
+          timestamp,
+          traceId: params.traceId
+        });
+      }
     }
 
     if (session?.status === "busy") {
@@ -1185,7 +1198,7 @@ export function createCodexStdioSessionManager(options = {}) {
         lastTraceId: optionalId(params.traceId),
         currentTraceId: null,
         turn: 0,
-        threadId: null,
+        threadId: requestedThreadId,
         durable: true,
         longLivedSession: true,
         codexStdio: true,
@@ -1193,9 +1206,11 @@ export function createCodexStdioSessionManager(options = {}) {
         secretMaterialStored: false
       };
       sessions.set(effectiveSessionId, session);
+      reused = Boolean(requestedThreadId);
     }
 
     session.conversationIds.add(conversationId);
+    session.threadId = requestedThreadId ?? session.threadId;
     session.workspace = params.workspace ?? session.workspace;
     session.sandbox = params.sandbox ?? session.sandbox;
     session.status = "busy";
diff --git a/internal/cloud/server-code-agent-http.ts b/internal/cloud/server-code-agent-http.ts
index 3cb8a5a4..72837d2d 100644
--- a/internal/cloud/server-code-agent-http.ts
+++ b/internal/cloud/server-code-agent-http.ts
@@ -583,6 +583,7 @@ async function recordCodeAgentSessionOwner({ payload = {}, params = {}, options
       ownerUserId,
       ownerRole: options.actor?.role ?? params.ownerRole ?? null,
       sessionId,
+      projectId: params.projectId ?? payload.projectId ?? null,
       conversationId,
       threadId,
       traceId,
@@ -618,6 +619,7 @@ function codeAgentSessionOwnerEvidence(payload = {}, params = {}) {
     sessionId: payload.sessionId ?? payload.session?.sessionId ?? payload.sessionReuse?.sessionId ?? params.sessionId ?? null,
     threadId: payload.session?.threadId ?? payload.sessionReuse?.threadId ?? payload.threadId ?? params.threadId ?? null,
     traceId: payload.traceId ?? params.traceId ?? null,
+    projectId: payload.projectId ?? params.projectId ?? null,
     secretMaterialStored: false,
     valuesRedacted: true
   };
diff --git a/internal/cloud/server.ts b/internal/cloud/server.ts
index 2f8f695f..04c69c50 100644
--- a/internal/cloud/server.ts
+++ b/internal/cloud/server.ts
@@ -314,6 +314,22 @@ async function handleRestAdapter(request, response, url, options) {
     return;
   }
 
+  if (url.pathname === "/v1/agent/conversations" && request.method === "GET") {
+    await options.accessController.listAgentConversations(request, response, url);
+    return;
+  }
+
+  const agentConversationMatch = url.pathname.match(/^\/v1\/agent\/conversations\/([^/]+)$/u);
+  if (agentConversationMatch && request.method === "GET") {
+    await options.accessController.getAgentConversation(request, response, decodeURIComponent(agentConversationMatch[1]));
+    return;
+  }
+
+  if (agentConversationMatch && (request.method === "PUT" || request.method === "PATCH")) {
+    await options.accessController.updateAgentConversation(request, response, decodeURIComponent(agentConversationMatch[1]));
+    return;
+  }
+
   if (url.pathname === "/v1/access/status" || url.pathname === "/v1/setup/status") {
     await options.accessController.handleAccessStatusRoute(request, response, url);
     return;
diff --git a/tools/hwlab-cli/client.test.ts b/tools/hwlab-cli/client.test.ts
index 26bfd8d2..1c8f9184 100644
--- a/tools/hwlab-cli/client.test.ts
+++ b/tools/hwlab-cli/client.test.ts
@@ -163,6 +163,137 @@ test("hwlab-cli client agent trace shows assistant stream text in compact output
   assert.equal(result.payload.body.eventsCount, 1);
 });
 
+test("hwlab-cli client agent trace auto logs in when protected trace has no local session", async () => {
+  const cwd = await mkdtemp(path.join(os.tmpdir(), "hwlab-cli-client-auth-"));
+  const calls: any[] = [];
+  const result = await runHwlabCli([
+    "client",
+    "agent",
+    "trace",
+    "trc_protected",
+    "--base-url",
+    "http://web.test",
+    "--username",
+    "admin"
+  ], {
+    cwd,
+    env: { HWLAB_PASSWORD: "secret-password" },
+    fetchImpl: async (url, init) => {
+      calls.push({ url: String(url), init, body: init?.body ? JSON.parse(String(init.body)) : null });
+      if (String(url).endsWith("/auth/login")) {
+        return new Response(JSON.stringify({ authenticated: true, user: { username: "admin" } }), {
+          status: 200,
+          headers: { "set-cookie": "hwlab_session=session-auto; Path=/; HttpOnly" }
+        });
+      }
+      return new Response(JSON.stringify({ status: "completed", traceId: "trc_protected", events: [] }), { status: 200 });
+    },
+    now: () => "2026-05-31T07:20:00.000Z"
+  });
+
+  assert.equal(result.exitCode, 0);
+  assert.deepEqual(calls.map((call) => call.url), [
+    "http://web.test/auth/login",
+    "http://web.test/v1/agent/chat/trace/trc_protected"
+  ]);
+  assert.equal(calls[1].init.headers.cookie, "hwlab_session=session-auto");
+  assert.equal(JSON.stringify(result.payload).includes("secret-password"), false);
+  const session = JSON.parse(await readFile(path.join(cwd, ".state/hwlab-cli/session.json"), "utf8"));
+  assert.equal(session.cookie, "hwlab_session=session-auto");
+});
+
+test("hwlab-cli client agent result refreshes expired session after 401 and reports compact result", async () => {
+  const cwd = await mkdtemp(path.join(os.tmpdir(), "hwlab-cli-client-auth-refresh-"));
+  await runHwlabCli(["client", "auth", "login", "--base-url", "http://web.test", "--username", "admin", "--password", "old"], {
+    cwd,
+    fetchImpl: async () => new Response(JSON.stringify({ authenticated: true, user: { username: "admin" } }), { status: 200, headers: { "set-cookie": "hwlab_session=session-old; Path=/" } })
+  });
+  const calls: any[] = [];
+  const result = await runHwlabCli([
+    "client",
+    "agent",
+    "result",
+    "trc_refresh",
+    "--base-url",
+    "http://web.test",
+    "--username",
+    "admin"
+  ], {
+    cwd,
+    env: { HWLAB_PASSWORD: "new-password" },
+    fetchImpl: async (url, init) => {
+      calls.push({ url: String(url), init, body: init?.body ? JSON.parse(String(init.body)) : null });
+      if (String(url).endsWith("/auth/login")) {
+        return new Response(JSON.stringify({ authenticated: true, user: { username: "admin" } }), {
+          status: 200,
+          headers: { "set-cookie": "hwlab_session=session-new; Path=/" }
+        });
+      }
+      if (init?.headers?.cookie === "hwlab_session=session-old") {
+        return new Response(JSON.stringify({ error: { code: "auth_required" } }), { status: 401 });
+      }
+      return new Response(JSON.stringify({ status: "completed", traceId: "trc_refresh", reply: { role: "assistant", content: "done" } }), { status: 200 });
+    },
+    sleep: async () => {},
+    now: () => "2026-05-31T07:21:00.000Z"
+  });
+
+  assert.equal(result.exitCode, 0);
+  assert.deepEqual(calls.map((call) => call.url), [
+    "http://web.test/v1/agent/chat/result/trc_refresh",
+    "http://web.test/auth/login",
+    "http://web.test/v1/agent/chat/result/trc_refresh"
+  ]);
+  assert.equal(calls[0].init.headers.cookie, "hwlab_session=session-old");
+  assert.equal(calls[2].init.headers.cookie, "hwlab_session=session-new");
+  assert.equal(result.payload.action, "client.agent.result");
+  assert.equal(result.payload.body.assistantText, "done");
+});
+
+test("hwlab-cli client protected agent commands return structured auth diagnosis for forbidden trace", async () => {
+  const result = await runHwlabCli(["client", "agent", "trace", "trc_forbidden", "--base-url", "http://web.test", "--cookie", "hwlab_session=session-a"], {
+    fetchImpl: async () => new Response(JSON.stringify({ error: { code: "agent_session_owner_required" } }), { status: 403 })
+  });
+
+  assert.equal(result.exitCode, 1);
+  assert.equal(result.payload.httpStatus, 403);
+  assert.equal(result.payload.authDiagnosis.code, "auth_forbidden");
+  assert.equal(result.payload.authDiagnosis.cookieSource, "explicit");
+  assert.match(result.payload.authDiagnosis.message, /无权访问/u);
+});
+
+test("hwlab-cli client agent inspect builds protected inspect query", async () => {
+  const calls: any[] = [];
+  const result = await runHwlabCli([
+    "client",
+    "agent",
+    "inspect",
+    "--trace-id",
+    "trc_inspect",
+    "--conversation-id",
+    "cnv_inspect",
+    "--session-id",
+    "ses_inspect",
+    "--thread-id",
+    "thread-1",
+    "--base-url",
+    "http://web.test",
+    "--cookie",
+    "hwlab_session=session-a"
+  ], {
+    fetchImpl: async (url, init) => {
+      calls.push({ url: String(url), init });
+      return new Response(JSON.stringify({ ok: true, status: "found", latestTraceId: "trc_inspect" }), { status: 200 });
+    }
+  });
+
+  assert.equal(result.exitCode, 0);
+  assert.equal(calls[0].url, "http://web.test/v1/agent/chat/inspect?traceId=trc_inspect&conversationId=cnv_inspect&sessionId=ses_inspect&threadId=thread-1");
+  assert.equal(calls[0].init.headers.cookie, "hwlab_session=session-a");
+  assert.equal(result.payload.action, "client.agent.inspect");
+  assert.equal(result.payload.body.status, "found");
+});
+
 test("hwlab-cli client harness submits waits and audits trace friction", async () => {
   const calls: any[] = [];
   const result = await runHwlabCli([
diff --git a/tools/src/hwlab-cli-lib.ts b/tools/src/hwlab-cli-lib.ts
index 2a28fec6..f4d82c6c 100644
--- a/tools/src/hwlab-cli-lib.ts
+++ b/tools/src/hwlab-cli-lib.ts
@@ -1,4 +1,4 @@
-import { mkdir, readFile, rm, writeFile } from "node:fs/promises";
+import { chmod, mkdir, readFile, rm, writeFile } from "node:fs/promises";
 import path from "node:path";
 
 const VERSION = "0.2.0-client";
@@ -84,7 +84,9 @@ function help() {
       "hwlab-cli client request GET /v1/access/status [--full]",
       "hwlab-cli client rpc system.health [--full]",
       "hwlab-cli client agent send --message TEXT --provider-profile deepseek --timeout-ms 120000",
+      "hwlab-cli client agent result TRACE_ID",
       "hwlab-cli client agent trace TRACE_ID",
+      "hwlab-cli client agent inspect --trace-id TRACE_ID",
       "hwlab-cli client agent cancel TRACE_ID",
       "hwlab-cli client harness submit --message TEXT --provider-profile deepseek",
       "hwlab-cli client harness wait TRACE_ID --timeout-ms 55000",
@@ -267,12 +269,23 @@ async function devicePodProbe(context: any, podId: string) {
 async function agentCommand(context: any) {
   const subcommand = context.rest[0] || "send";
   if (subcommand === "send") return agentSend(context);
+  if (subcommand === "result") {
+    const traceId = requiredTraceId(context.rest[1] ?? context.parsed.traceId);
+    const pathName = `/v1/agent/chat/result/${encodeURIComponent(traceId)}`;
+    const response = await requestJson({ ...context, method: "GET", path: pathName });
+    return responsePayload("client.agent.result", response, context, { route: route("GET", pathName), traceId, body: responseBodyForCli(response.body, context.parsed) });
+  }
   if (subcommand === "trace") {
-    const traceId = requiredText(context.rest[1] ?? context.parsed.traceId, "traceId");
+    const traceId = requiredTraceId(context.rest[1] ?? context.parsed.traceId);
     const pathName = `/v1/agent/chat/trace/${encodeURIComponent(traceId)}`;
     const response = await requestJson({ ...context, method: "GET", path: pathName });
     return responsePayload("client.agent.trace", response, context, { route: route("GET", pathName), traceId, body: responseBodyForCli(response.body, context.parsed) });
   }
+  if (subcommand === "inspect") {
+    const pathName = agentInspectPath(context);
+    const response = await requestJson({ ...context, method: "GET", path: pathName });
+    return responsePayload("client.agent.inspect", response, context, { route: route("GET", pathName), body: responseBodyForCli(response.body, context.parsed) });
+  }
   if (subcommand === "cancel") {
     const traceId = requiredText(context.rest[1] ?? context.parsed.traceId, "traceId");
     const response = await requestJson({ ...context, method: "POST", path: "/v1/agent/chat/cancel", body: clean({ traceId, conversationId: text(context.parsed.conversationId), sessionId: text(context.parsed.sessionId) }), extraHeaders: { "x-trace-id": traceId } });
@@ -281,6 +294,22 @@ async function agentCommand(context: any) {
   throw cliError("unsupported_agent_command", `unsupported agent command: ${subcommand}`, { subcommand });
 }
 
+function agentInspectPath(context: any) {
+  const params = new URLSearchParams();
+  const traceId = text(context.rest[1] ?? context.parsed.traceId);
+  const conversationId = text(context.parsed.conversationId);
+  const sessionId = text(context.parsed.sessionId);
+  const threadId = text(context.parsed.threadId);
+  if (traceId) params.set("traceId", requiredTraceId(traceId));
+  if (conversationId) params.set("conversationId", conversationId);
+  if (sessionId) params.set("sessionId", sessionId);
+  if (threadId) params.set("threadId", threadId);
+  if ([...params.keys()].length === 0) {
+    throw cliError("missing_inspect_query", "client agent inspect requires --trace-id, --conversation-id, --session-id, or --thread-id");
+  }
+  return `/v1/agent/chat/inspect?${params.toString()}`;
+}
+
 async function harnessCommand(context: any) {
   const subcommand = context.rest[0] || "help";
   if (["help", "--help", "-h"].includes(subcommand)) return harnessHelp();
@@ -647,26 +676,91 @@ function normalizeRequestPath(value: string) {
   return pathName;
 }
 
-async function requestJson({ parsed, env, fetchImpl, cwd, method, path: pathName, body, auth = true, extraHeaders = {}, timeoutMs }: any) {
+async function requestJson(context: any) {
+  const { parsed, env, cwd, method, path: pathName, body, auth = true, extraHeaders = {}, timeoutMs } = context;
   const url = `${baseUrl(parsed, env)}${pathName}`;
   const controller = new AbortController();
   const timer = setTimeout(() => controller.abort(), timeoutMs ?? numberOption(parsed.timeoutMs) ?? DEFAULT_TIMEOUT_MS);
   try {
-    const cookie = auth ? await authCookie({ parsed, env, cwd: cwd ?? process.cwd() }) : null;
-    const headers = clean({
-      accept: "application/json",
-      ...(body ? { "content-type": "application/json" } : {}),
-      ...(cookie ? { cookie } : {}),
-      ...extraHeaders
-    });
-    const response = await fetchImpl(url, { method, headers, body: body ? JSON.stringify(body) : undefined, signal: controller.signal });
-    const textBody = await response.text();
-    return { status: response.status, headers: response.headers, body: parseJson(textBody), url, method, path: pathName };
+    const effectiveAuth = auth && parsed.noAuth !== true;
+    const explicitCookie = explicitAuthCookie(parsed, env);
+    const session = effectiveAuth && !explicitCookie && parsed.noSession !== true
+      ? await loadSession({ parsed, env, cwd: cwd ?? process.cwd() })
+      : null;
+    let cookie = effectiveAuth ? explicitCookie || session?.cookie || null : null;
+    const authState: any = {
+      required: effectiveAuth,
+      cookieSource: cookie ? explicitCookie ? "explicit" : "state" : null,
+      autoLoginAttempted: false,
+      autoLoginStatus: null,
+      retryAfterLogin: false
+    };
+    if (effectiveAuth && !cookie && autoAuthAllowed(parsed)) {
+      const login = await autoLoginSession(context, controller.signal);
+      authState.autoLoginAttempted = true;
+      authState.autoLoginStatus = login.status;
+      authState.cookieSource = login.cookie ? "auto-login" : null;
+      cookie = login.cookie ?? null;
+    }
+    let response = await sendJsonRequest({ context, url, method, body, cookie, extraHeaders, signal: controller.signal, pathName });
+    if (effectiveAuth && response.status === 401 && !explicitCookie && autoAuthAllowed(parsed)) {
+      const login = await autoLoginSession(context, controller.signal, { force: true });
+      authState.autoLoginAttempted = true;
+      authState.autoLoginStatus = login.status;
+      if (login.cookie) {
+        authState.cookieSource = "auto-login";
+        authState.retryAfterLogin = true;
+        cookie = login.cookie;
+        response = await sendJsonRequest({ context, url, method, body, cookie, extraHeaders, signal: controller.signal, pathName });
+      }
+    }
+    return { ...response, authDiagnosis: authDiagnosis(response, authState) };
   } finally {
     clearTimeout(timer);
   }
 }
 
+async function sendJsonRequest({ context, url, method, body, cookie, extraHeaders, signal, pathName }: any) {
+  const headers = clean({
+    accept: "application/json",
+    ...(body ? { "content-type": "application/json" } : {}),
+    ...(cookie ? { cookie } : {}),
+    ...extraHeaders
+  });
+  const response = await context.fetchImpl(url, { method, headers, body: body ? JSON.stringify(body) : undefined, signal });
+  const textBody = await response.text();
+  return { status: response.status, headers: response.headers, body: parseJson(textBody), url, method, path: pathName };
+}
+
+async function autoLoginSession(context: any, signal: AbortSignal, { force = false } = {}) {
+  const password = await optionalPasswordValue(context);
+  if (!password) return { status: "credentials_missing", cookie: null };
+  const username = text(context.parsed.username ?? context.env.HWLAB_USERNAME) || "admin";
+  const response = await sendJsonRequest({
+    context,
+    url: `${baseUrl(context.parsed, context.env)}/auth/login`,
+    method: "POST",
+    pathName: "/auth/login",
+    body: { username, password },
+    cookie: null,
+    extraHeaders: {},
+    signal
+  });
+  const cookie = cookieFromResponse(response);
+  const success = isHttpSuccess(response) && response.body?.authenticated === true && cookie;
+  if (success) {
+    await saveSession(context, {
+      baseUrl: baseUrl(context.parsed, context.env),
+      cookie,
+      user: safeUser(response.body?.user ?? response.body?.actor),
+      expiresAt: textOrNull(response.body?.expiresAt),
+      updatedAt: context.now(),
+      refreshedAfter401: force === true || undefined
+    });
+  }
+  return { status: success ? "succeeded" : `failed_http_${response.status}`, cookie: success ? cookie : null };
+}
+
 function parseOptions(argv: string[]): ParsedArgs {
   const out: ParsedArgs = { _: [] };
   for (let index = 0; index < argv.length; index += 1) {
@@ -684,9 +778,14 @@ function parseOptions(argv: string[]): ParsedArgs {
 }
 
 async function passwordValue({ parsed, env, stdinText }: any) {
-  if (typeof parsed.passwordEnv === "string") return requiredText(env[parsed.passwordEnv], parsed.passwordEnv);
+  const password = await optionalPasswordValue({ parsed, env, stdinText });
+  return requiredText(password, "password");
+}
+
+async function optionalPasswordValue({ parsed, env, stdinText }: any) {
+  if (typeof parsed.passwordEnv === "string") return text(env[parsed.passwordEnv]);
   if (parsed.passwordStdin === true) return stdinText !== undefined ? stdinText.trimEnd() : await readStdin();
-  return requiredText(parsed.password ?? env.HWLAB_PASSWORD, "password");
+  return text(parsed.password ?? env.HWLAB_PASSWORD);
 }
 
 async function readStdin() {
@@ -700,13 +799,22 @@ function baseUrl(parsed: ParsedArgs, env: EnvLike) {
 }
 
 async function authCookie({ parsed, env, cwd }: { parsed: ParsedArgs; env: EnvLike; cwd: string }) {
-  const explicit = text(parsed.cookie ?? env.HWLAB_SESSION_COOKIE);
+  const explicit = explicitAuthCookie(parsed, env);
   if (explicit) return explicit.includes("=") ? explicit : `hwlab_session=${encodeURIComponent(explicit)}`;
   if (parsed.noSession === true) return null;
   const session = await loadSession({ parsed, env, cwd });
   return session?.cookie ?? null;
 }
 
+function explicitAuthCookie(parsed: ParsedArgs, env: EnvLike) {
+  const explicit = text(parsed.cookie ?? env.HWLAB_SESSION_COOKIE);
+  return explicit ? explicit.includes("=") ? explicit : `hwlab_session=${encodeURIComponent(explicit)}` : null;
+}
+
+function autoAuthAllowed(parsed: ParsedArgs) {
+  return parsed.noAuth !== true && parsed.noAutoAuth !== true;
+}
+
 async function loadSession({ parsed, env, cwd }: { parsed: ParsedArgs; env: EnvLike; cwd: string }) {
   try {
     const raw = await readFile(stateFile(parsed, cwd), "utf8");
@@ -722,7 +830,8 @@ async function loadSession({ parsed, env, cwd }: { parsed: ParsedArgs; env: EnvL
 async function saveSession(context: any, session: Record<string, unknown>) {
   const file = stateFile(context.parsed, context.cwd);
   await mkdir(path.dirname(file), { recursive: true });
-  await writeFile(file, `${JSON.stringify(session, null, 2)}\n`, "utf8");
+  await writeFile(file, `${JSON.stringify(session, null, 2)}\n`, { encoding: "utf8", mode: 0o600 });
+  await chmod(file, 0o600).catch(() => {});
 }
 
 async function clearSession(context: any) {
@@ -752,11 +861,41 @@ function responsePayload(action: string, response: any, context: any, extra: Rec
     baseUrl: baseUrl(context.parsed, context.env),
     httpStatus: response.status,
     route: extra.route ?? route(response.method, response.path),
+    ...(response.authDiagnosis ? { authDiagnosis: response.authDiagnosis } : {}),
     ...extra,
     body: extra.body ?? response.body
   };
 }
 
+function authDiagnosis(response: any, authState: any) {
+  if (!authState?.required) return null;
+  if (response.status !== 401 && response.status !== 403) return null;
+  if (response.status === 403) {
+    return {
+      code: "auth_forbidden",
+      status: "forbidden",
+      message: "当前账号无权访问该受保护资源，可能是 trace/result 不属于当前 owner，或当前用户不是 admin。",
+      httpStatus: response.status,
+      cookieSource: authState.cookieSource,
+      autoLoginAttempted: authState.autoLoginAttempted,
+      retryAfterLogin: authState.retryAfterLogin
+    };
+  }
+  const missingCredentials = authState.autoLoginAttempted && authState.autoLoginStatus === "credentials_missing";
+  return {
+    code: missingCredentials ? "auth_credentials_missing" : "auth_required_or_expired",
+    status: missingCredentials ? "credentials_missing" : "unauthorized",
+    message: missingCredentials
+      ? "需要登录后访问该受保护资源；请提供 --password-env、--password、--password-stdin 或 HWLAB_PASSWORD，让 CLI 自动登录。"
+      : "登录态不存在或已过期；CLI 已按可用凭据尝试自动登录，仍未通过认证。",
+    httpStatus: response.status,
+    cookieSource: authState.cookieSource,
+    autoLoginAttempted: authState.autoLoginAttempted,
+    autoLoginStatus: authState.autoLoginStatus,
+    retryAfterLogin: authState.retryAfterLogin
+  };
+}
+
 function compactProbe(method: string, pathName: string, response: any) {
   return { ok: isHttpSuccess(response) && response.body?.ok !== false, httpStatus: response.status, route: route(method, pathName), body: compactApiBody(response.body) };
 }
diff --git a/web/hwlab-cloud-web/app.ts b/web/hwlab-cloud-web/app.ts
index 32728189..da76f72f 100644
--- a/web/hwlab-cloud-web/app.ts
+++ b/web/hwlab-cloud-web/app.ts
@@ -244,6 +244,9 @@ const state = {
 };
 
 let codeAgentSessionPersistTimer = null;
+let accountConversationHydrated = false;
+let accountConversationPersistInFlight = false;
+let accountConversationPersistPending = false;
 
 restoreCodeAgentSessionState();
 
@@ -260,7 +263,6 @@ initConversationScrollMemory();
 initCommandBar();
 initLiveBuildOverlay();
 initWorkbenchLogout(el.logoutButton);
-el.logoutButton.addEventListener("click", clearCodeAgentSessionState);
 initGateControls();
 installWorkbenchTestHooks();
 renderStaticWorkbench();
@@ -268,6 +270,7 @@ renderProbePending();
 renderCodeAgentSummary();
 loadHelpSurface();
 loadLiveSurface().then(renderLiveSurface);
+hydrateAccountCodeAgentSessionState();
 window.setTimeout(refreshRestoredCodeAgentTraces, 0);
 
 function byId(id) {
@@ -460,7 +463,17 @@ function persistCodeAgentSessionState() {
     clearCodeAgentSessionState();
     return;
   }
-  const payload = {
+  const payload = codeAgentSessionSnapshotPayload();
+  try {
+    window.localStorage?.setItem(CODE_AGENT_SESSION_STORAGE_KEY, JSON.stringify(payload));
+  } catch {
+    // Keep the in-memory conversation when localStorage is unavailable or full.
+  }
+  persistAccountCodeAgentSessionState(payload);
+}
+
+function codeAgentSessionSnapshotPayload() {
+  return {
     version: CODE_AGENT_SESSION_STORAGE_VERSION,
     updatedAtMs: Date.now(),
     conversationId: state.conversationId,
@@ -469,11 +482,117 @@ function persistCodeAgentSessionState() {
     sessionStatus: state.sessionStatus,
     chatMessages: state.chatMessages.slice(-CODE_AGENT_SESSION_STORAGE_MESSAGE_LIMIT).map(storedChatMessage)
   };
-  try {
-    window.localStorage?.setItem(CODE_AGENT_SESSION_STORAGE_KEY, JSON.stringify(payload));
-  } catch {
-    // Keep the in-memory conversation when localStorage is unavailable or full.
+}
+
+async function hydrateAccountCodeAgentSessionState() {
+  const response = await fetchJson(`/v1/agent/conversations?projectId=${encodeURIComponent(WORKBENCH_PROJECT_ID)}&limit=1`, {
+    timeoutMs: Math.min(API_TIMEOUT_MS, 5000),
+    timeoutName: "Code Agent account conversation hydrate"
+  });
+  if (!response.ok) return;
+  const conversation = response.data?.defaultConversation ?? (Array.isArray(response.data?.conversations) ? response.data.conversations[0] : null);
+  if (!conversation) {
+    accountConversationHydrated = true;
+    if (state.conversationId) persistCodeAgentSessionState();
+    return;
   }
+  const payload = accountConversationToStoredSessionPayload(conversation);
+  if (!payload) return;
+  const shouldReplace = !state.conversationId || Number(payload.updatedAtMs) > latestLocalCodeAgentSessionUpdatedAt();
+  if (!shouldReplace) {
+    accountConversationHydrated = true;
+    persistCodeAgentSessionState();
+    return;
+  }
+  state.conversationId = nonEmptyString(payload.conversationId);
+  state.sessionId = nonEmptyString(payload.sessionId);
+  state.threadId = nonEmptyString(payload.threadId);
+  state.sessionStatus = nonEmptyString(payload.sessionStatus);
+  state.chatMessages = Array.isArray(payload.chatMessages)
+    ? payload.chatMessages.map(restoreStoredChatMessage).filter(Boolean)
+    : [];
+  accountConversationHydrated = true;
+  persistCodeAgentSessionState();
+  renderAgentChatStatus(latestChatResult()?.status ?? "idle", latestChatResult());
+  renderCodeAgentSummary();
+  renderConversation();
+  renderDrafts();
+  window.setTimeout(refreshRestoredCodeAgentTraces, 0);
+}
+
+function accountConversationToStoredSessionPayload(conversation) {
+  if (!conversation || typeof conversation !== "object") return null;
+  const conversationId = nonEmptyString(conversation.conversationId);
+  if (!conversationId) return null;
+  const messages = Array.isArray(conversation.messages) ? conversation.messages : [];
+  const updatedAtMs = Date.parse(conversation.updatedAt ?? conversation.snapshot?.updatedAt ?? "");
+  return {
+    version: CODE_AGENT_SESSION_STORAGE_VERSION,
+    updatedAtMs: Number.isFinite(updatedAtMs) ? updatedAtMs : Date.now(),
+    conversationId,
+    sessionId: nonEmptyString(conversation.sessionId ?? conversation.session?.sessionId),
+    threadId: nonEmptyString(conversation.threadId ?? conversation.session?.threadId),
+    sessionStatus: nonEmptyString(conversation.snapshot?.sessionStatus ?? conversation.status),
+    chatMessages: messages.slice(-CODE_AGENT_SESSION_STORAGE_MESSAGE_LIMIT)
+  };
+}
+
+function latestLocalCodeAgentSessionUpdatedAt() {
+  let latest = 0;
+  for (const message of state.chatMessages) {
+    const value = Date.parse(message.updatedAt ?? message.createdAt ?? "");
+    if (Number.isFinite(value) && value > latest) latest = value;
+  }
+  return latest;
+}
+
+function persistAccountCodeAgentSessionState(payload) {
+  if (!accountConversationHydrated) return;
+  if (!payload.conversationId) return;
+  accountConversationPersistPending = true;
+  if (accountConversationPersistInFlight) return;
+  void flushAccountCodeAgentSessionState();
+}
+
+async function flushAccountCodeAgentSessionState() {
+  accountConversationPersistInFlight = true;
+  try {
+    while (accountConversationPersistPending) {
+      accountConversationPersistPending = false;
+      const payload = codeAgentSessionSnapshotPayload();
+      if (!payload.conversationId) continue;
+      await fetchJson(`/v1/agent/conversations/${encodeURIComponent(payload.conversationId)}`, {
+        method: "PUT",
+        headers: { "Content-Type": "application/json" },
+        timeoutMs: Math.min(API_TIMEOUT_MS, 5000),
+        timeoutName: "Code Agent account conversation persist",
+        body: JSON.stringify({
+          projectId: WORKBENCH_PROJECT_ID,
+          conversationId: payload.conversationId,
+          sessionId: payload.sessionId,
+          threadId: payload.threadId,
+          sessionStatus: payload.sessionStatus,
+          lastTraceId: latestTraceIdFromStoredMessages(payload.chatMessages),
+          messages: payload.chatMessages,
+          snapshot: {
+            source: "cloud-web-account-sync",
+            updatedAt: new Date(payload.updatedAtMs).toISOString(),
+            sessionStatus: payload.sessionStatus
+          }
+        })
+      });
+    }
+  } finally {
+    accountConversationPersistInFlight = false;
+  }
+}
+
+function latestTraceIdFromStoredMessages(messages) {
+  for (const message of [...(messages ?? [])].reverse()) {
+    const traceId = nonEmptyString(message?.traceId ?? message?.runnerTrace?.traceId);
+    if (traceId) return traceId;
+  }
+  return null;
 }
 
 function clearCodeAgentSessionState() {