feat: align session sidebar and cli management

internal/cloud/access-control.test.ts

@@ -1263,6 +1263,34 @@ test("cloud api stores and restores Code Agent conversations by authenticated ac
     assert.equal(bobDirect.status, 404);
     assert.equal(bobDirect.body.error.code, "agent_conversation_not_found");
 
+    const workspace = await getJson(port, "/v1/workbench/workspace?projectId=prj_device_pod_workbench", aliceLogin.cookie);
+    assert.equal(workspace.status, 200);
+    const selected = await postJson(port, `/v1/workbench/workspace/${workspace.body.workspace.workspaceId}/select-conversation`, {
+      projectId: "prj_device_pod_workbench",
+      conversationId: "cnv_account_sync",
+      updatedByClient: "test-suite"
+    }, aliceLogin.cookie);
+    assert.equal(selected.status, 200);
+    assert.equal(selected.body.workspace.selectedConversationId, "cnv_account_sync");
+
+    const deleted = await deleteJson(port, "/v1/agent/conversations/cnv_account_sync", {
+      projectId: "prj_device_pod_workbench",
+      workspaceId: workspace.body.workspace.workspaceId,
+      updatedByClient: "test-suite"
+    }, aliceLogin.cookie);
+    assert.equal(deleted.status, 200);
+    assert.equal(deleted.body.status, "deleted");
+    assert.equal(deleted.body.archivedCount, 1);
+    assert.equal(deleted.body.workspace.selectedConversationId, null);
+
+    const afterDeleteList = await getJson(port, "/v1/agent/conversations?projectId=prj_device_pod_workbench", aliceLogin.cookie);
+    assert.equal(afterDeleteList.status, 200);
+    assert.equal(afterDeleteList.body.count, 0);
+
+    const archivedDirect = await getJson(port, "/v1/agent/conversations/cnv_account_sync", aliceLogin.cookie);
+    assert.equal(archivedDirect.status, 200);
+    assert.equal(archivedDirect.body.conversation.status, "archived");
+
     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" });
@@ -2114,6 +2142,23 @@ async function getJson(port, path, cookie = null, extraHeaders = {}) {
   };
 }
 
+async function deleteJson(port, path, body = {}, cookie = null, extraHeaders = {}) {
+  const response = await fetch(`http://127.0.0.1:${port}${path}`, {
+    method: "DELETE",
+    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 requestJson(request) {
   const chunks = [];
   for await (const chunk of request) chunks.push(chunk);

internal/cloud/access-control.ts

@@ -612,6 +612,7 @@ class AccessController {
       ownerScoped: true,
       projectId,
       limit,
+      includeArchived: false,
       now: this.now()
     }) ?? [];
     const conversations = conversationsFromAgentSessions(sessions);
@@ -640,6 +641,7 @@ class AccessController {
       ownerScoped: true,
       conversationId,
       limit: 20,
+      includeArchived: true,
       now: this.now()
     }) ?? [];
     const conversation = conversationsFromAgentSessions(sessions).find((item) => item.conversationId === conversationId) ?? null;
@@ -671,6 +673,62 @@ class AccessController {
     return sendJson(response, 200, { ok: true, status: "stored", contractVersion: "agent-conversations-v1", conversation });
   }
 
+  async deleteAgentConversation(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 projectId = textOr(body.projectId, "prj_device_pod_workbench");
+    const visible = await this.visibleConversationForActor(auth.actor, conversationId, projectId, { includeArchived: true });
+    if (!visible) return sendJson(response, 404, errorPayload("agent_conversation_not_found", "Agent conversation is not visible to the current actor", 404));
+    const archived = await this.store.archiveAgentConversation?.({
+      ownerUserId: auth.actor.id,
+      actorRole: auth.actor.role,
+      ownerScoped: true,
+      conversationId,
+      projectId,
+      now: this.now()
+    });
+    let workspace = null;
+    const workspaceId = textOr(body.workspaceId, "");
+    if (safeWorkspaceId(workspaceId)) {
+      const current = await this.store.getWorkspaceForUser?.({ workspaceId, ownerUserId: auth.actor.id, actorRole: auth.actor.role });
+      if (current?.selectedConversationId === conversationId) {
+        const next = await this.nextVisibleConversationForActor(auth.actor, projectId, conversationId);
+        workspace = await this.store.updateWorkspace?.({
+          workspaceId,
+          ownerUserId: auth.actor.id,
+          actorRole: auth.actor.role,
+          selectedConversationId: next?.conversationId ?? null,
+          selectedAgentSessionId: next?.sessionId ?? null,
+          activeTraceId: null,
+          patch: {
+            selectedConversationId: next?.conversationId ?? null,
+            selectedAgentSessionId: next?.sessionId ?? null,
+            activeTraceId: null,
+            messages: next?.messages ?? [],
+            deletedConversationId: conversationId,
+            source: "workbench-delete-conversation"
+          },
+          updatedBySessionId: currentSessionIdFromAuth(auth),
+          updatedByClient: textOr(body.updatedByClient ?? body.client, "unknown"),
+          now: this.now()
+        });
+      }
+    }
+    return sendJson(response, 200, {
+      ok: true,
+      status: "deleted",
+      contractVersion: "agent-conversations-v1",
+      conversationId,
+      archivedCount: archived?.count ?? 0,
+      workspace: workspace ? await this.publicWorkbenchWorkspace(workspace, auth.actor) : null
+    });
+  }
+
   async getWorkbenchWorkspace(request, response, url) {
     await this.ensureBootstrap();
     const auth = await this.authenticate(request, { required: true });
@@ -971,7 +1029,7 @@ class AccessController {
     });
   }
 
-  async visibleConversationForActor(actor, conversationId, projectId = "") {
+  async visibleConversationForActor(actor, conversationId, projectId = "", options = {}) {
     if (!safeConversationIdLocal(conversationId)) return null;
     const sessions = await this.store.listAgentSessionsForUser?.({
       ownerUserId: actor.id,
@@ -980,11 +1038,25 @@ class AccessController {
       conversationId,
       projectId: textOr(projectId, ""),
       limit: 20,
+      includeArchived: options.includeArchived === true,
       now: this.now()
     }) ?? [];
     return conversationsFromAgentSessions(sessions).find((item) => item.conversationId === conversationId) ?? null;
   }
 
+  async nextVisibleConversationForActor(actor, projectId = "", excludedConversationId = "") {
+    const sessions = await this.store.listAgentSessionsForUser?.({
+      ownerUserId: actor.id,
+      actorRole: actor.role,
+      ownerScoped: true,
+      projectId: textOr(projectId, ""),
+      limit: 20,
+      includeArchived: false,
+      now: this.now()
+    }) ?? [];
+    return conversationsFromAgentSessions(sessions).find((item) => item.conversationId !== excludedConversationId) ?? null;
+  }
+
   async requireGrantTargets({ devicePodId, userId }) {
     const pod = await this.store.getDevicePod(devicePodId);
     if (!pod || pod.status !== "active") {
@@ -1416,9 +1488,26 @@ class MemoryAccessStore {
       .filter((session) => input.ownerScoped === true || role !== "admin" ? session.ownerUserId === ownerUserId : true)
       .filter((session) => !projectId || session.projectId === projectId)
       .filter((session) => !conversationId || session.conversationId === conversationId)
+      .filter((session) => input.includeArchived === true || session.status !== "archived")
       .sort((a, b) => String(b.updatedAt ?? "").localeCompare(String(a.updatedAt ?? "")))
       .slice(0, limit);
   }
+  async archiveAgentConversation(input = {}) {
+    const ownerUserId = textOr(input.ownerUserId, "");
+    const role = textOr(input.actorRole, "user");
+    const conversationId = textOr(input.conversationId, "");
+    const projectId = textOr(input.projectId, "");
+    const now = input.now ?? this.now();
+    let count = 0;
+    for (const [id, session] of this.agentSessions.entries()) {
+      if ((input.ownerScoped === true || role !== "admin") && session.ownerUserId !== ownerUserId) continue;
+      if (conversationId && session.conversationId !== conversationId) continue;
+      if (projectId && session.projectId !== projectId) continue;
+      this.agentSessions.set(id, { ...session, status: "archived", endedAt: session.endedAt ?? now, updatedAt: now });
+      count += 1;
+    }
+    return { count };
+  }
   async getOrCreateDefaultWorkspace(input = {}) {
     const ownerUserId = textOr(input.ownerUserId, "");
     const projectId = textOr(input.projectId, "prj_device_pod_workbench");
@@ -1529,11 +1618,34 @@ class PostgresAccessStore extends MemoryAccessStore {
       params.push(conversationId);
       clauses.push(`conversation_id = $${params.length}`);
     }
+    if (input.includeArchived !== true) clauses.push("status <> 'archived'");
     params.push(limit);
     const sql = `SELECT id, project_id, agent_id, status, started_at, ended_at, owner_user_id, conversation_id, thread_id, last_trace_id, session_json, updated_at FROM agent_sessions ${clauses.length ? `WHERE ${clauses.join(" AND ")}` : ""} ORDER BY updated_at DESC NULLS LAST LIMIT $${params.length}`;
     const result = await this.query(sql, params);
     return result.rows.map(pgAgentSession);
   }
+  async archiveAgentConversation(input = {}) {
+    await this.ensureSchema();
+    const role = textOr(input.actorRole, "user");
+    const ownerUserId = textOr(input.ownerUserId, "");
+    const conversationId = textOr(input.conversationId, "");
+    const projectId = textOr(input.projectId, "");
+    const now = input.now ?? this.now();
+    const clauses = ["conversation_id = $1"];
+    const params = [conversationId];
+    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}`);
+    }
+    params.push(now);
+    const sql = `UPDATE agent_sessions SET status = 'archived', ended_at = COALESCE(ended_at, $${params.length}), updated_at = $${params.length} WHERE ${clauses.join(" AND ")} RETURNING id`;
+    const result = await this.query(sql, params);
+    return { count: result.rows?.length ?? 0 };
+  }
   async getOrCreateDefaultWorkspace(input = {}) {
     await this.ensureSchema();
     const ownerUserId = textOr(input.ownerUserId, "");
@@ -1849,6 +1961,7 @@ function threadResumeFailureThreadId(result = {}) {
   ), 240) || null;
 }
 function terminalWorkbenchSessionStatus(result = {}) {
+  if (isThreadResumeFailedResult(result)) return "failed";
   const sessionStatus = textOr(result.session?.status ?? result.sessionSummary?.status ?? result.sessionLifecycleStatus ?? result.runnerTrace?.sessionStatus, "").toLowerCase();
   if (sessionStatus && sessionStatus !== "running" && sessionStatus !== "busy" && sessionStatus !== "pending") return sessionStatus === "cancelled" ? "canceled" : sessionStatus;
   const status = textOr(result.status ?? result.agentRun?.terminalStatus, "").toLowerCase();

internal/cloud/server.ts

@@ -334,6 +334,11 @@ async function handleRestAdapter(request, response, url, options) {
     return;
   }
 
+  if (agentConversationMatch && request.method === "DELETE") {
+    await options.accessController.deleteAgentConversation(request, response, decodeURIComponent(agentConversationMatch[1]));
+    return;
+  }
+
   if (url.pathname === "/v1/workbench/workspace" && request.method === "GET") {
     await options.accessController.getWorkbenchWorkspace(request, response, url);
     return;

internal/dev-entrypoint/cloud-web-routes.mjs

@@ -49,7 +49,10 @@ export function isCloudApiProxyRoute(method, pathname) {
       isWorkbenchWorkspaceWriteProxyRoute(normalizedMethod, normalizedPath);
   }
   if (normalizedMethod === "PATCH" || normalizedMethod === "PUT") {
-    return isWorkbenchWorkspaceWriteProxyRoute(normalizedMethod, normalizedPath);
+    return isWorkbenchWorkspaceWriteProxyRoute(normalizedMethod, normalizedPath) || isAgentConversationWriteProxyRoute(normalizedMethod, normalizedPath);
+  }
+  if (normalizedMethod === "DELETE") {
+    return isAgentConversationWriteProxyRoute(normalizedMethod, normalizedPath);
   }
   return false;
 }
@@ -70,6 +73,12 @@ function isWorkbenchWorkspaceWriteProxyRoute(method, pathname) {
   return false;
 }
 
+function isAgentConversationWriteProxyRoute(method, pathname) {
+  const parts = pathname.split("/").filter(Boolean);
+  if (parts.length !== 4 || parts[0] !== "v1" || parts[1] !== "agent" || parts[2] !== "conversations") return false;
+  return ["PUT", "PATCH", "DELETE"].includes(method);
+}
+
 function isPublicCodeAgentPollRoute(method, pathname) {
   return method === "GET" && (
     pathname.startsWith("/v1/agent/chat/result/") ||

internal/dev-entrypoint/cloud-web-routes.test.mjs

@@ -92,3 +92,12 @@ test("cloud web proxies Code Agent steer through the Web-equivalent public API p
     routeKey: "POST /v1/agent/chat/steer"
   });
 });
+
+test("cloud web proxies authenticated session deletion through account conversation API", () => {
+  assert.deepEqual(cloudWebProxyRoutePolicy("DELETE", "/v1/agent/conversations/cnv_test"), {
+    proxy: true,
+    authRequired: true,
+    publicRoute: false,
+    routeKey: "DELETE /v1/agent/conversations/cnv_test"
+  });
+});

tools/hwlab-cli/client.test.ts

@@ -171,9 +171,66 @@ test("hwlab-cli client group help is visible and does not issue HTTP requests",
   assert.equal(agent.payload.action, "client.agent.help");
   assert.equal(agent.payload.serviceRuntime, false);
   assert.ok(agent.payload.commands.some((command: string) => command.startsWith("send ")));
+
+  const session = await runHwlabCli(["client", "session", "--help", "--base-url", "http://web.test"], { fetchImpl });
+  assert.equal(session.exitCode, 0);
+  assert.equal(session.payload.action, "client.session.help");
+  assert.equal(session.payload.webEquivalent, true);
+  assert.ok(session.payload.commands.some((command: string) => command.startsWith("create ")));
   assert.equal(fetchCount, 0);
 });
 
+test("hwlab-cli client session management uses Cloud Web workspace and conversation paths", async () => {
+  const cwd = await mkdtemp(path.join(os.tmpdir(), "hwlab-cli-session-management-"));
+  const calls: any[] = [];
+  const fetchImpl = async (url: string | URL, init: any = {}) => {
+    const body = init?.body ? JSON.parse(String(init.body)) : null;
+    calls.push({ url: String(url), method: init?.method ?? "GET", body });
+    if (String(url).endsWith("/v1/workbench/workspace?projectId=prj_device_pod_workbench")) {
+      return new Response(JSON.stringify({ ok: true, workspace: { workspaceId: "wsp_cli_session", revision: 4, selectedConversationId: "cnv_existing", selectedAgentSessionId: "ses_existing", workspace: {} } }), { status: 200 });
+    }
+    if (String(url).endsWith("/v1/workbench/workspace/wsp_cli_session/select-conversation")) {
+      const conversationId = body.conversationId || "cnv_created";
+      const sessionId = body.sessionId || "ses_created";
+      return new Response(JSON.stringify({
+        ok: true,
+        workspace: {
+          workspaceId: "wsp_cli_session",
+          revision: 5,
+          selectedConversationId: conversationId,
+          selectedAgentSessionId: sessionId,
+          selectedConversation: { conversationId, sessionId, threadId: body.threadId || "thread-cli", status: "active", messages: [] },
+          workspace: {}
+        }
+      }), { status: 200 });
+    }
+    if (String(url).endsWith("/v1/agent/conversations/cnv_existing")) {
+      return new Response(JSON.stringify({ ok: true, status: "deleted", archivedCount: 1, conversationId: "cnv_existing", workspace: { workspaceId: "wsp_cli_session", revision: 6, selectedConversationId: null, selectedAgentSessionId: null, workspace: {} } }), { status: 200 });
+    }
+    return new Response(JSON.stringify({ ok: false, error: { code: "unexpected_test_route" } }), { status: 404 });
+  };
+
+  const created = await runHwlabCli(["client", "session", "create", "--base-url", "http://web.test", "--cookie", "hwlab_session=session-a", "--conversation-id", "cnv_created", "--session-id", "ses_created", "--thread-id", "thread-created"], { cwd, fetchImpl });
+  const switched = await runHwlabCli(["client", "session", "switch", "cnv_existing", "--base-url", "http://web.test", "--cookie", "hwlab_session=session-a", "--session-id", "ses_existing", "--thread-id", "thread-existing"], { cwd, fetchImpl });
+  const deleted = await runHwlabCli(["client", "session", "delete", "cnv_existing", "--confirm", "--base-url", "http://web.test", "--cookie", "hwlab_session=session-a"], { cwd, fetchImpl });
+
+  assert.equal(created.exitCode, 0);
+  assert.equal(switched.exitCode, 0);
+  assert.equal(deleted.exitCode, 0);
+  assert.equal(calls[1].url, "http://web.test/v1/workbench/workspace/wsp_cli_session/select-conversation");
+  assert.equal(calls[1].method, "POST");
+  assert.equal(calls[1].body.create, true);
+  assert.equal(calls[1].body.updatedByClient, "hwlab-cli");
+  assert.equal(calls[3].url, "http://web.test/v1/workbench/workspace/wsp_cli_session/select-conversation");
+  assert.equal(calls[3].body.conversationId, "cnv_existing");
+  assert.equal(calls[5].url, "http://web.test/v1/agent/conversations/cnv_existing");
+  assert.equal(calls[5].method, "DELETE");
+  assert.equal(calls[5].body.workspaceId, "wsp_cli_session");
+  assert.equal(created.payload.route.path, "/v1/workbench/workspace/wsp_cli_session/select-conversation");
+  assert.equal(switched.payload.current.conversationId, "cnv_existing");
+  assert.equal(deleted.payload.body.status, "deleted");
+});
+
 test("hwlab-cli rejects manual endpoint override in locked assembled runtime", async () => {
   const result = await runHwlabCli(["client", "auth", "status", "--base-url", "http://74.48.78.17:17666"], {
     env: {

tools/src/hwlab-cli-lib.ts

@@ -72,6 +72,7 @@ async function clientCommand(context: any) {
   if (group === "runtime") return runtimeCommand(next);
   if (group === "gateway") return gatewayCommand(next);
   if (group === "agent") return agentCommand(next);
+  if (group === "session" || group === "sessions") return sessionCommand(next);
   if (["harness", "harness-ops", "harness-opt"].includes(group)) return harnessCommand(next);
   if (group === "workbench") return workbenchCommand(next);
   if (group === "rpc") return rpcCommand(next);
@@ -85,6 +86,7 @@ function clientSubcommandHelp(group: string) {
   if (group === "runtime") return runtimeHelp();
   if (group === "gateway") return gatewayHelp();
   if (group === "agent") return agentHelp();
+  if (group === "session" || group === "sessions") return sessionHelp();
   if (["harness", "harness-ops", "harness-opt"].includes(group)) return harnessHelp();
   if (group === "workbench") return workbenchHelp();
   if (group === "rpc") return rpcHelp();
@@ -117,6 +119,10 @@ function help() {
       "hwlab-cli client runtime routes",
       "hwlab-cli client gateway sessions",
       "hwlab-cli client gateway pressure --gateway-session-id gws_D601_F103",
+      "hwlab-cli client session list",
+      "hwlab-cli client session create",
+      "hwlab-cli client session switch cnv_...",
+      "hwlab-cli client session delete cnv_... --confirm",
       "hwlab-cli client workbench summary --pod-id device-pod-71-freq",
       "hwlab-cli client workbench restore --profile NAME",
       "hwlab-cli client workbench status --profile NAME",
@@ -633,6 +639,128 @@ function agentHelp() {
   });
 }
 
+async function sessionCommand(context: any) {
+  const subcommand = context.rest[0] || "list";
+  if (wantsHelp(context)) return sessionHelp();
+  if (subcommand === "list" || subcommand === "ls") return sessionListCommand(context);
+  if (subcommand === "current" || subcommand === "status") return sessionCurrentCommand(context);
+  if (subcommand === "create" || subcommand === "new") return sessionCreateCommand(context);
+  if (subcommand === "switch" || subcommand === "select") return sessionSwitchCommand(context);
+  if (subcommand === "delete" || subcommand === "rm") return sessionDeleteCommand(context);
+  throw cliError("unsupported_session_command", `unsupported session command: ${subcommand}`, { subcommand });
+}
+
+function sessionHelp() {
+  return ok("client.session.help", {
+    serviceRuntime: false,
+    imagePublished: false,
+    webEquivalent: true,
+    commands: [
+      "list [--limit N]",
+      "current",
+      "create [--conversation-id ID] [--session-id ID] [--thread-id ID]",
+      "switch CONVERSATION_ID|--conversation-id ID",
+      "delete CONVERSATION_ID|--conversation-id ID --confirm"
+    ]
+  });
+}
+
+async function sessionListCommand(context: any) {
+  const projectId = text(context.parsed.projectId) || DEFAULT_WORKBENCH_PROJECT_ID;
+  const limit = numberOption(context.parsed.limit) ?? 100;
+  const pathName = `/v1/agent/conversations?projectId=${encodeURIComponent(projectId)}&limit=${encodeURIComponent(String(limit))}`;
+  const response = await requestJson({ ...context, method: "GET", path: pathName });
+  return responsePayload("client.session.list", response, context, {
+    route: route("GET", pathName),
+    sessions: sessionSummaries(response.body?.conversations),
+    body: responseBodyForCli(response.body, context.parsed)
+  });
+}
+
+async function sessionCurrentCommand(context: any) {
+  const workspace = await restoreWorkbenchWorkspace(context, { quiet: false });
+  return ok("client.session.current", {
+    baseUrl: baseUrl(context.parsed, context.env),
+    runtimeEndpoint: runtimeEndpointVisibility(runtimeEndpoint(context.parsed, context.env, "web")),
+    route: route("GET", `/v1/workbench/workspace?projectId=${encodeURIComponent(text(context.parsed.projectId) || DEFAULT_WORKBENCH_PROJECT_ID)}`),
+    workspace,
+    current: sessionSummary(workspace?.selectedConversation) ?? sessionSummary({
+      conversationId: workspace?.selectedConversationId,
+      sessionId: workspace?.selectedAgentSessionId,
+      threadId: workspace?.threadId,
+      status: workspace?.sessionStatus,
+      lastTraceId: workspace?.activeTraceId,
+      updatedAt: workspace?.updatedAt
+    })
+  });
+}
+
+async function sessionCreateCommand(context: any) {
+  const workspace = await restoreWorkbenchWorkspace(context, { quiet: false });
+  const workspaceId = text(context.parsed.workspaceId) || text(workspace?.workspaceId);
+  if (!workspaceId) throw cliError("workspace_restore_required", "session create requires a restored workspace or --workspace-id", { nextCommand: "client workbench restore" });
+  const conversationId = safeOptionalConversationId(context.parsed.conversationId);
+  const sessionId = safeOptionalSessionId(context.parsed.sessionId);
+  const pathName = `/v1/workbench/workspace/${encodeURIComponent(workspaceId)}/select-conversation`;
+  const response = await requestJson({
+    ...context,
+    method: "POST",
+    path: pathName,
+    body: clean({
+      projectId: text(context.parsed.projectId) || DEFAULT_WORKBENCH_PROJECT_ID,
+      create: true,
+      conversationId,
+      sessionId,
+      threadId: text(context.parsed.threadId),
+      updatedByClient: "hwlab-cli"
+    })
+  });
+  if (responseSucceeded(response) && response.body?.workspace) await saveWorkspaceState(context, response.body.workspace);
+  return responsePayload("client.session.create", response, context, { route: route("POST", pathName), workspace: normalizeWorkbenchWorkspace(response.body?.workspace), current: sessionSummary(response.body?.workspace?.selectedConversation), body: responseBodyForCli(response.body, context.parsed) });
+}
+
+async function sessionSwitchCommand(context: any) {
+  const conversationId = requiredConversationId(context.rest[1] ?? context.parsed.conversationId);
+  const workspace = await restoreWorkbenchWorkspace(context, { quiet: false });
+  const workspaceId = text(context.parsed.workspaceId) || text(workspace?.workspaceId);
+  if (!workspaceId) throw cliError("workspace_restore_required", "session switch requires a restored workspace or --workspace-id", { nextCommand: "client workbench restore" });
+  const pathName = `/v1/workbench/workspace/${encodeURIComponent(workspaceId)}/select-conversation`;
+  const response = await requestJson({
+    ...context,
+    method: "POST",
+    path: pathName,
+    body: clean({
+      projectId: text(context.parsed.projectId) || DEFAULT_WORKBENCH_PROJECT_ID,
+      conversationId,
+      sessionId: safeOptionalSessionId(context.parsed.sessionId),
+      threadId: text(context.parsed.threadId),
+      updatedByClient: "hwlab-cli"
+    })
+  });
+  if (responseSucceeded(response) && response.body?.workspace) await saveWorkspaceState(context, response.body.workspace);
+  return responsePayload("client.session.switch", response, context, { route: route("POST", pathName), workspace: normalizeWorkbenchWorkspace(response.body?.workspace), current: sessionSummary(response.body?.workspace?.selectedConversation), body: responseBodyForCli(response.body, context.parsed) });
+}
+
+async function sessionDeleteCommand(context: any) {
+  const conversationId = requiredConversationId(context.rest[1] ?? context.parsed.conversationId);
+  if (context.parsed.confirm !== true) throw cliError("session_delete_confirmation_required", "session delete requires --confirm", { flag: "--confirm", conversationId });
+  const workspace = await restoreWorkbenchWorkspace(context, { quiet: true });
+  const workspaceId = text(context.parsed.workspaceId) || text(workspace?.workspaceId);
+  const pathName = `/v1/agent/conversations/${encodeURIComponent(conversationId)}`;
+  const response = await requestJson({
+    ...context,
+    method: "DELETE",
+    path: pathName,
+    body: clean({
+      projectId: text(context.parsed.projectId) || DEFAULT_WORKBENCH_PROJECT_ID,
+      workspaceId,
+      updatedByClient: "hwlab-cli"
+    })
+  });
+  if (responseSucceeded(response) && response.body?.workspace) await saveWorkspaceState(context, response.body.workspace);
+  return responsePayload("client.session.delete", response, context, { route: route("DELETE", pathName), workspace: normalizeWorkbenchWorkspace(response.body?.workspace), body: responseBodyForCli(response.body, context.parsed) });
+}
+
 async function agentComposer(context: any) {
   const subcommand = context.rest[1] || "status";
   if (subcommand === "status") return agentComposerStatus(context);
@@ -1875,6 +2003,24 @@ function normalizeWorkbenchWorkspace(workspace: any) {
   });
 }
 
+function sessionSummaries(conversations: any) {
+  return Array.isArray(conversations) ? conversations.map(sessionSummary).filter(Boolean) : [];
+}
+
+function sessionSummary(conversation: any) {
+  if (!conversation || typeof conversation !== "object") return null;
+  return clean({
+    conversationId: text(conversation.conversationId),
+    sessionId: text(conversation.sessionId ?? conversation.session?.sessionId),
+    threadId: text(conversation.threadId ?? conversation.session?.threadId),
+    status: text(conversation.status ?? conversation.snapshot?.sessionStatus),
+    lastTraceId: text(conversation.lastTraceId),
+    updatedAt: text(conversation.updatedAt),
+    messageCount: Array.isArray(conversation.messages) ? conversation.messages.length : undefined,
+    valuesRedacted: conversation.valuesRedacted === true ? true : undefined
+  });
+}
+
 function workbenchThreadId(workspace: any, workspaceJson: any) {
   const selectedConversation = workspace?.selectedConversation && typeof workspace.selectedConversation === "object" ? workspace.selectedConversation : {};
   const selectedAgentSession = workspace?.selectedAgentSession && typeof workspace.selectedAgentSession === "object" ? workspace.selectedAgentSession : {};
@@ -2257,6 +2403,28 @@ function requiredTraceId(value: unknown) {
   return result;
 }
 
+function requiredConversationId(value: unknown) {
+  const result = requiredText(value, "conversationId");
+  if (!/^cnv_[A-Za-z0-9_.:-]+$/u.test(result)) {
+    throw cliError("invalid_conversation_id", "conversationId must start with cnv_", { conversationId: result });
+  }
+  return result;
+}
+
+function safeOptionalConversationId(value: unknown) {
+  const result = text(value);
+  if (!result) return "";
+  if (!/^cnv_[A-Za-z0-9_.:-]+$/u.test(result)) throw cliError("invalid_conversation_id", "conversationId must start with cnv_", { conversationId: result });
+  return result;
+}
+
+function safeOptionalSessionId(value: unknown) {
+  const result = text(value);
+  if (!result) return "";
+  if (!/^ses_[A-Za-z0-9_.:-]+$/u.test(result)) throw cliError("invalid_session_id", "sessionId must start with ses_", { sessionId: result });
+  return result;
+}
+
 function preview(value: unknown, max = 500) {
   if (value === undefined || value === null) return null;
   const result = String(value).replace(/\s+/gu, " ").trim();

web/hwlab-cloud-web/app-conversation.ts

@@ -3,8 +3,6 @@ function renderConversation() {
   captureConversationScrollPosition();
   captureTraceScrollPositions();
   captureTraceBodyScrollPositions();
-  const sessionView = currentSessionView();
-  renderSessionTabs(sessionView);
   const introMessages = [
     {
       role: "system",
@@ -14,8 +12,7 @@ function renderConversation() {
     },
     codeAgentStatusMessage(state.codeAgentAvailability)
   ];
-  const messages = sessionView.tabs.length > 0 ? sessionView.messages : state.chatMessages;
-  replaceChildren(el.conversationList, ...[...introMessages, ...messages].map(messageCard));
+  replaceChildren(el.conversationList, ...[...introMessages, ...state.chatMessages].map(messageCard));
   restoreConversationScrollPosition();
   restoreTraceScrollPositions();
   restoreTraceBodyScrollPositions();
@@ -28,90 +25,6 @@ function renderConversation() {
   });
 }
 
-function currentSessionView() {
-  return sessionTabsFromMessages(state.chatMessages, {
-    activeSessionKey: activeSessionKeyFromRuntime({
-      activeSessionKey: state.activeSessionKey,
-      currentRequest: state.currentRequest,
-      sessionId: state.sessionId,
-      conversationId: state.conversationId,
-      activeTraceId: state.activeTraceId
-    })
-  });
-}
-
-function renderSessionTabs(sessionView) {
-  if (!el.sessionTabs) return;
-  if (!sessionView.tabs.length) {
-    state.activeSessionKey = null;
-    replaceChildren(el.sessionTabs);
-    el.sessionTabs.hidden = true;
-    return;
-  }
-  state.activeSessionKey = sessionView.activeKey;
-  el.sessionTabs.hidden = false;
-  replaceChildren(el.sessionTabs, ...sessionView.tabs.map(sessionTabButton));
-}
-
-function sessionTabButton(tab) {
-  const button = document.createElement("button");
-  button.type = "button";
-  button.className = `session-tab tone-border-${toneClass(sessionTabTone(tab))}`;
-  button.dataset.sessionKey = tab.key;
-  button.setAttribute("role", "tab");
-  button.setAttribute("aria-selected", tab.active ? "true" : "false");
-  button.setAttribute("aria-label", sessionTabAriaLabel(tab));
-  button.title = sessionTabTitle(tab);
-  button.append(
-    textSpan(tab.label, "session-tab-label"),
-    textSpan(tab.subtitle, "session-tab-subtitle"),
-    textSpan(`${tab.messageCount} 条`, "session-tab-count")
-  );
-  button.addEventListener("click", () => {
-    selectSessionTab(tab);
-    renderAgentChatStatus(deriveAgentChatStatus(), latestChatResultForActiveSession());
-    renderCodeAgentSummary();
-    renderConversation();
-  });
-  return button;
-}
-
-function selectSessionTab(tab) {
-  state.activeSessionKey = tab.key;
-  state.conversationId = tab.conversationId ?? state.conversationId;
-  state.sessionId = tab.sessionId ?? (String(tab.key).startsWith("ses_") || String(tab.key).startsWith("ses-") ? tab.key : state.sessionId);
-  state.threadId = tab.threadId ?? state.threadId;
-  state.activeTraceId = tab.running ? tab.lastTraceId ?? state.activeTraceId : null;
-  state.sessionStatus = tab.status ?? state.sessionStatus;
-  state.conversationScrollPosition = { top: 0, left: 0, bottomGap: 0 };
-}
-
-function latestChatResultForActiveSession() {
-  const sessionView = currentSessionView();
-  return [...sessionView.messages].reverse().find((message) => message.role === "agent") ?? latestChatResult();
-}
-
-function sessionTabTone(tab) {
-  if (tab.status === "running" || tab.running) return "pending";
-  if (["failed", "timeout", "error", "canceled"].includes(tab.status)) return "blocked";
-  if (tab.status === "completed") return "dev-live";
-  return "source";
-}
-
-function sessionTabTitle(tab) {
-  return [
-    `session=${tab.sessionId ?? "unknown"}`,
-    `conversation=${tab.conversationId ?? "unknown"}`,
-    `thread=${tab.threadId ?? "unknown"}`,
-    `trace=${tab.lastTraceId ?? "unknown"}`,
-    `messages=${tab.messageCount}`
-  ].join(" / ");
-}
-
-function sessionTabAriaLabel(tab) {
-  return `${tab.label}，${tab.messageCount} 条消息，${tab.subtitle}`;
-}
-
 function initConversationScrollMemory() {
   for (const eventName of ["wheel", "touchstart", "pointerdown"]) {
     el.conversationList.addEventListener(eventName, markConversationScrollIntent, { passive: true });

web/hwlab-cloud-web/app-device-pod.ts

@@ -169,6 +169,7 @@ async function submitAgentMessage(value, options = {}) {
   renderAgentChatStatus("running");
   renderCodeAgentSummary();
   renderConversation();
+  renderSessionSidebar();
   renderDrafts();
   renderDevicePodPanel(state.liveSurface);
 
@@ -197,6 +198,7 @@ async function submitAgentMessage(value, options = {}) {
     renderAgentChatStatus(updatedMessage?.status, state.chatMessages[index]);
     renderCodeAgentSummary();
     persistCodeAgentSessionState();
+    refreshSessionSidebar();
   } catch (error) {
     stopTraceStream();
     if (state.canceledTraces.has(traceId)) return;
@@ -239,6 +241,7 @@ async function submitAgentMessage(value, options = {}) {
     renderAgentChatStatus(failedStatus, state.chatMessages[index]);
     renderCodeAgentSummary();
     persistCodeAgentSessionState();
+    refreshSessionSidebar();
   } finally {
     if (state.currentRequest?.traceId === traceId) {
       state.currentRequest = null;
@@ -250,6 +253,7 @@ async function submitAgentMessage(value, options = {}) {
     stopTraceStream();
     renderCodeAgentSummary();
     renderConversation();
+    renderSessionSidebar();
     renderDrafts();
     renderDevicePodPanel(state.liveSurface);
   }
@@ -295,6 +299,7 @@ async function submitAgentSteer(value, options = {}) {
     renderAgentChatStatus(deriveAgentChatStatus(), latestChatResult());
     renderCodeAgentSummary();
     renderConversation();
+    refreshSessionSidebar();
     renderDrafts();
     renderDevicePodPanel(state.liveSurface);
   }
@@ -1063,6 +1068,7 @@ async function reconcileCodeAgentResult(messageId, options = {}) {
     renderAgentChatStatus(updated.status, updated);
     renderCodeAgentSummary();
     renderConversation();
+    refreshSessionSidebar();
     renderDrafts();
     renderDevicePodPanel(state.liveSurface);
     return true;

web/hwlab-cloud-web/app-session-tabs.ts

@@ -1,10 +1,12 @@
+const EMPTY_CONVERSATION_SESSION_LIST = Object.freeze({ tabs: [], activeKey: null, activeConversation: null });
+
 export function sessionTabsFromMessages(messages = [], options = {}) {
   const list = Array.isArray(messages) ? messages : [];
   const aliases = sessionAliasesFromMessages(list);
   const sessions = new Map();
   for (const message of list) {
     const key = sessionKeyFromMessage(message, aliases);
-    const existing = sessions.get(key) ?? createSessionTab(key, message);
+    const existing = sessions.get(key) ?? createMessageSessionTab(key, message);
     mergeMessageIntoSessionTab(existing, message);
     sessions.set(key, existing);
   }
@@ -13,8 +15,8 @@ export function sessionTabsFromMessages(messages = [], options = {}) {
     .map((tab, index) => ({
       ...tab,
       ordinal: index + 1,
-      label: tab.sessionId ? `Session ${shortSessionToken(tab.sessionId)}` : `会话 ${index + 1}`,
-      subtitle: tab.status === "running" ? "处理中" : tab.lastTraceId ? `trace ${shortSessionToken(tab.lastTraceId)}` : "无 trace"
+      label: tab.sessionId ? `Session ${shortToken(tab.sessionId)}` : `会话 ${index + 1}`,
+      subtitle: tab.status === "running" ? "处理中" : tab.lastTraceId ? `trace ${shortToken(tab.lastTraceId)}` : "无 trace"
     }));
   const preferredKey = firstNonEmptyString(options.activeSessionKey, options.sessionId, options.conversationId, options.traceId);
   const activeKey = resolveActiveSessionKey(tabs, preferredKey);
@@ -25,6 +27,28 @@ export function sessionTabsFromMessages(messages = [], options = {}) {
   };
 }
 
+export function sessionTabsFromConversations(conversations = [], options = {}) {
+  const selectedConversationId = firstNonEmptyString(options.selectedConversationId, options.conversationId);
+  const selectedSessionId = firstNonEmptyString(options.selectedSessionId, options.sessionId);
+  const selectedTraceId = firstNonEmptyString(options.activeTraceId, options.traceId);
+  const tabs = (Array.isArray(conversations) ? conversations : [])
+    .map((conversation) => sessionTabFromConversation(conversation))
+    .filter(Boolean)
+    .sort((left, right) => right.lastTimestampMs - left.lastTimestampMs)
+    .map((tab, index) => ({
+      ...tab,
+      ordinal: index + 1,
+      label: tab.title || `Session ${index + 1}`,
+      subtitle: conversationSessionTabSubtitle(tab),
+      active: conversationSessionTabMatches(tab, selectedConversationId, selectedSessionId, selectedTraceId)
+    }));
+  if (tabs.length === 0) return { ...EMPTY_CONVERSATION_SESSION_LIST };
+  let active = tabs.find((tab) => tab.active) ?? tabs[0];
+  const normalized = tabs.map((tab) => ({ ...tab, active: tab.key === active.key }));
+  active = normalized.find((tab) => tab.key === active.key) ?? normalized[0];
+  return { tabs: normalized, activeKey: active?.key ?? null, activeConversation: active ?? null };
+}
+
 export function sessionKeyFromMessage(message = {}, aliases = {}) {
   const traceId = firstNonEmptyString(message?.traceId, message?.runnerTrace?.traceId);
   const conversationId = firstNonEmptyString(message?.conversationId, message?.runnerTrace?.conversationId);
@@ -55,7 +79,32 @@ export function activeSessionKeyFromRuntime(input = {}) {
   );
 }
 
-function createSessionTab(key, message) {
+export function sessionTabFromConversation(conversation = {}) {
+  const conversationId = firstNonEmptyString(conversation.conversationId);
+  if (!conversationId) return null;
+  const sessionId = firstNonEmptyString(conversation.sessionId, conversation.session?.sessionId);
+  const messages = Array.isArray(conversation.messages) ? conversation.messages : [];
+  const lastMessage = newestMessage(messages);
+  const updatedAt = firstNonEmptyString(lastMessage?.updatedAt, conversation.updatedAt, conversation.snapshot?.updatedAt, lastMessage?.createdAt, conversation.startedAt);
+  const lastTimestampMs = timestampMs(updatedAt);
+  const status = normalizedStatus(firstNonEmptyString(conversation.snapshot?.sessionStatus, conversation.status, lastMessage?.status));
+  const lastTraceId = firstNonEmptyString(conversation.lastTraceId, lastMessage?.traceId, lastMessage?.runnerTrace?.traceId);
+  return {
+    key: sessionId || conversationId,
+    conversationId,
+    sessionId,
+    threadId: firstNonEmptyString(conversation.threadId, conversation.session?.threadId, lastMessage?.threadId, lastMessage?.session?.threadId),
+    lastTraceId,
+    status,
+    title: conversationSessionTitle(conversation, sessionId, conversationId),
+    messageCount: messages.length,
+    lastTimestampMs,
+    updatedAt,
+    lastMessagePreview: firstNonEmptyString(lastMessage?.text, lastMessage?.title, conversation.snapshot?.source)
+  };
+}
+
+function createMessageSessionTab(key, message) {
   const timestampMs = timestampFromMessage(message);
   return {
     key,
@@ -64,7 +113,7 @@ function createSessionTab(key, message) {
     threadId: firstNonEmptyString(message?.threadId, message?.session?.threadId, message?.sessionReuse?.threadId, message?.providerTrace?.threadId, message?.runnerTrace?.threadId),
     firstTraceId: firstNonEmptyString(message?.traceId, message?.runnerTrace?.traceId),
     lastTraceId: firstNonEmptyString(message?.traceId, message?.runnerTrace?.traceId),
-    status: normalizedStatus(sessionStatusFromMessage(message)),
+    status: normalizedStatus(messageSessionStatusFromMessage(message)),
     messageCount: 0,
     agentCount: 0,
     userCount: 0,
@@ -99,7 +148,7 @@ function mergeMessageIntoSessionTab(tab, message) {
   tab.messageCount += 1;
   if (message?.role === "agent") tab.agentCount += 1;
   if (message?.role === "user") tab.userCount += 1;
-  const messageStatus = normalizedStatus(sessionStatusFromMessage(message));
+  const messageStatus = normalizedStatus(messageSessionStatusFromMessage(message));
   tab.running = tab.running || messageStatus === "running";
   tab.status = tab.running ? "running" : messageStatus || tab.status;
   tab.firstTimestampMs = Math.min(tab.firstTimestampMs, timestampMs);
@@ -116,11 +165,10 @@ function resolveActiveSessionKey(tabs, preferredKey) {
 }
 
 function timestampFromMessage(message) {
-  const timestamp = Date.parse(message?.updatedAt ?? message?.createdAt ?? message?.runnerTrace?.updatedAt ?? "");
-  return Number.isFinite(timestamp) ? timestamp : 0;
+  return timestampMs(message?.updatedAt ?? message?.createdAt ?? message?.runnerTrace?.updatedAt);
 }
 
-function sessionStatusFromMessage(message) {
+function messageSessionStatusFromMessage(message) {
   return firstNonEmptyString(
     message?.sessionLifecycleStatus,
     message?.sessionSummary?.status,
@@ -133,11 +181,39 @@ function sessionStatusFromMessage(message) {
   );
 }
 
+function conversationSessionTitle(conversation, sessionId, conversationId) {
+  const explicit = firstNonEmptyString(conversation.title, conversation.name, conversation.snapshot?.title);
+  if (explicit) return explicit;
+  const token = shortToken(sessionId || conversationId);
+  return `Session ${token}`;
+}
+
+function conversationSessionTabSubtitle(tab) {
+  if (["running", "busy", "pending", "active"].includes(tab.status)) return "处理中";
+  if (tab.lastTraceId) return `trace ${shortToken(tab.lastTraceId)}`;
+  if (tab.threadId) return `thread ${shortToken(tab.threadId)}`;
+  return "未开始";
+}
+
+function conversationSessionTabMatches(tab, conversationId, sessionId, traceId) {
+  const values = [tab.key, tab.conversationId, tab.sessionId, tab.lastTraceId].filter(Boolean);
+  return Boolean(values.includes(conversationId) || values.includes(sessionId) || values.includes(traceId));
+}
+
+function newestMessage(messages) {
+  return [...messages].sort((left, right) => timestampMs(right?.updatedAt ?? right?.createdAt) - timestampMs(left?.updatedAt ?? left?.createdAt))[0] ?? null;
+}
+
+function timestampMs(value) {
+  const timestamp = Date.parse(String(value ?? ""));
+  return Number.isFinite(timestamp) ? timestamp : 0;
+}
+
 function normalizedStatus(value) {
   return String(value ?? "source").trim().toLowerCase() || "source";
 }
 
-function shortSessionToken(value) {
+function shortToken(value) {
   const text = String(value ?? "").trim();
   if (!text) return "unknown";
   const parts = text.split(/[-_:]/u).filter(Boolean);

web/hwlab-cloud-web/app.ts

@@ -9,9 +9,9 @@ import {
 import { classifyCodeAgentStatusSummary, codeAgentAvailabilityFromLive } from "./code-agent-status.ts";
 import { computeCodeAgentComposerState } from "./composer-policy.ts";
 import { classifyWorkbenchLiveStatus } from "./live-status.ts";
+import { activeSessionKeyFromRuntime, sessionTabsFromConversations, sessionTabsFromMessages } from "./app-session-tabs.ts";
 import { marked } from "./third_party/marked/marked.esm.js";
 import { hardenRenderedMarkdown, renderMessageMarkdown } from "./message-markdown.ts";
-import { activeSessionKeyFromRuntime, sessionTabsFromMessages } from "./app-session-tabs.ts";
 
 const DEFAULT_API_TIMEOUT_MS = 4500;
 const WORKBENCH_PROJECT_ID = "prj_device_pod_workbench";
@@ -133,6 +133,9 @@ const el = {
   codeAgentSummaryTrace: byId("code-agent-summary-trace"),
   codeAgentSummaryDetail: byId("code-agent-summary-detail"),
   sessionTabs: byId("session-tabs"),
+  sessionCreate: byId("session-create"),
+  sessionDelete: byId("session-delete"),
+  sessionStatus: byId("session-status"),
   conversationList: byId("conversation-list"),
   gateSourceStatus: byId("gate-source-status"),
   gateStatusFilter: byId("gate-status-filter"),
@@ -210,6 +213,13 @@ const state = {
   canceledTraces: new Set(),
   currentRequest: null,
   sessionStatus: null,
+  sessionList: {
+    loading: false,
+    error: null,
+    items: [],
+    loadedAt: null,
+    pendingAction: null
+  },
   chatPending: false,
   liveSurface: null,
   gateDiagnostics: {
@@ -271,6 +281,7 @@ initLeftSidebarResize();
 initRightSidebarResize();
 initDevicePodPanel();
 initSkillsPanel();
+initSessionSidebar();
 initCodeAgentTimeoutControl();
 initConversationScrollMemory();
 initCommandBar();
@@ -519,6 +530,7 @@ async function hydrateAccountCodeAgentSessionState() {
   });
   if (!response.ok) return;
   applyWorkbenchWorkspace(response.data?.workspace);
+  loadSessionSidebar({ quiet: true });
   const conversation = response.data?.workspace?.selectedConversation ?? null;
   const payload = conversation
     ? accountConversationToStoredSessionPayload(conversation)
@@ -561,6 +573,7 @@ function applyWorkbenchWorkspace(workspace) {
   state.activeTraceId = nonEmptyString(workspace.activeTraceId ?? workspace.workspace?.activeTraceId) ?? state.activeTraceId;
   state.conversationId = nonEmptyString(workspace.selectedConversationId) ?? nonEmptyString(workspace.workspace?.selectedConversationId) ?? state.conversationId;
   state.sessionId = nonEmptyString(workspace.selectedAgentSessionId) ?? nonEmptyString(workspace.workspace?.selectedAgentSessionId) ?? state.sessionId;
+  state.threadId = nonEmptyString(workspace.selectedConversation?.threadId ?? workspace.selectedConversation?.session?.threadId ?? workspace.workspace?.threadId) ?? state.threadId;
   state.sessionStatus = nonEmptyString(workspace.workspace?.sessionStatus) ?? state.sessionStatus;
   CODE_AGENT_PROVIDER_PROFILE = normalizeCodeAgentProviderProfile(workspace.providerProfile ?? workspace.workspace?.providerProfile ?? CODE_AGENT_PROVIDER_PROFILE);
   syncCodeAgentTimeoutControl();
@@ -568,6 +581,259 @@ function applyWorkbenchWorkspace(workspace) {
   return workspace;
 }
 
+function initSessionSidebar() {
+  renderSessionSidebar();
+  el.sessionCreate.addEventListener("click", () => createSessionSidebarSession());
+  el.sessionDelete.addEventListener("click", () => deleteCurrentSessionSidebarSession());
+}
+
+async function loadSessionSidebar(options = {}) {
+  state.sessionList.loading = true;
+  state.sessionList.error = null;
+  renderSessionSidebar();
+  const response = await fetchJson(`/v1/agent/conversations?projectId=${encodeURIComponent(WORKBENCH_PROJECT_ID)}&limit=100`, {
+    timeoutMs: Math.min(API_TIMEOUT_MS, 5000),
+    timeoutName: "Code Agent session list"
+  });
+  state.sessionList.loading = false;
+  if (!response.ok) {
+    state.sessionList.error = response.error || "session list unavailable";
+    if (options.quiet !== true) renderSessionSidebar();
+    return false;
+  }
+  state.sessionList.items = Array.isArray(response.data?.conversations) ? response.data.conversations : [];
+  state.sessionList.loadedAt = new Date().toISOString();
+  renderSessionSidebar();
+  return true;
+}
+
+function refreshSessionSidebar(options = {}) {
+  if (state.sessionList.loading) return;
+  void loadSessionSidebar({ quiet: options.quiet !== false });
+}
+
+function renderSessionSidebar() {
+  const view = sessionTabsFromConversations(sessionSidebarConversations(), {
+    selectedConversationId: state.conversationId,
+    selectedSessionId: state.sessionId,
+    activeTraceId: state.activeTraceId
+  });
+  replaceChildren(el.sessionTabs, ...view.tabs.map(sessionTabButton));
+  const pending = Boolean(state.sessionList.pendingAction);
+  el.sessionCreate.disabled = pending;
+  el.sessionDelete.disabled = pending || !view.activeConversation?.conversationId;
+  el.sessionStatus.textContent = sessionSidebarStatusText(view.tabs.length);
+  el.sessionStatus.title = state.sessionList.error || state.sessionList.loadedAt || "session list not loaded";
+}
+
+function sessionSidebarConversations() {
+  const items = Array.isArray(state.sessionList.items) ? [...state.sessionList.items] : [];
+  if (state.conversationId && !items.some((item) => item?.conversationId === state.conversationId)) {
+    items.unshift(currentStateConversationSnapshot());
+  }
+  return items.filter(Boolean);
+}
+
+function currentStateConversationSnapshot() {
+  return {
+    conversationId: state.conversationId,
+    sessionId: state.sessionId,
+    threadId: state.threadId,
+    status: state.sessionStatus || deriveAgentChatStatus(),
+    lastTraceId: activeTraceIdFromStoredMessages(state.chatMessages) || state.activeTraceId,
+    updatedAt: new Date().toISOString(),
+    messages: state.chatMessages
+  };
+}
+
+function sessionSidebarStatusText(count) {
+  if (state.sessionList.pendingAction === "create") return "创建中";
+  if (state.sessionList.pendingAction === "switch") return "切换中";
+  if (state.sessionList.pendingAction === "delete") return "删除中";
+  if (state.sessionList.loading) return count > 0 ? `刷新中 / ${count} 个` : "加载中";
+  if (state.sessionList.error) return "列表受阻";
+  return count > 0 ? `${count} 个 session` : "无 session";
+}
+
+function sessionTabButton(tab) {
+  const button = document.createElement("button");
+  button.type = "button";
+  button.className = `session-tab tone-border-${toneClass(sessionTabTone(tab))}`;
+  button.dataset.conversationId = tab.conversationId;
+  button.dataset.sessionId = tab.sessionId || "";
+  button.setAttribute("role", "tab");
+  button.setAttribute("aria-selected", tab.active ? "true" : "false");
+  button.setAttribute("aria-label", `${tab.label}，${tab.subtitle}，${tab.messageCount} 条消息`);
+  button.title = sessionTabTitle(tab);
+  button.append(
+    textSpan(tab.label, "session-tab-label"),
+    textSpan(tab.subtitle, "session-tab-subtitle"),
+    textSpan(`${tab.messageCount} 条`, "session-tab-count")
+  );
+  button.addEventListener("click", () => selectSessionSidebarSession(tab));
+  return button;
+}
+
+function sessionTabTone(tab) {
+  if (["running", "busy", "pending", "active"].includes(tab.status)) return "pending";
+  if (["failed", "timeout", "error", "canceled", "archived"].includes(tab.status)) return "blocked";
+  if (["completed", "idle"].includes(tab.status)) return "dev-live";
+  return "source";
+}
+
+function sessionTabTitle(tab) {
+  return [
+    `conversation=${tab.conversationId ?? "unknown"}`,
+    `session=${tab.sessionId ?? "unknown"}`,
+    `thread=${tab.threadId ?? "unknown"}`,
+    `trace=${tab.lastTraceId ?? "unknown"}`
+  ].join(" / ");
+}
+
+async function ensureWorkbenchWorkspace() {
+  if (state.workspaceId) return true;
+  const response = await fetchJson(`/v1/workbench/workspace?projectId=${encodeURIComponent(WORKBENCH_PROJECT_ID)}`, {
+    timeoutMs: Math.min(API_TIMEOUT_MS, 5000),
+    timeoutName: "Workbench workspace restore"
+  });
+  if (!response.ok) {
+    state.sessionList.error = response.error || "workspace restore failed";
+    renderSessionSidebar();
+    return false;
+  }
+  applyWorkbenchWorkspace(response.data?.workspace);
+  return Boolean(state.workspaceId);
+}
+
+async function createSessionSidebarSession() {
+  if (!(await ensureWorkbenchWorkspace())) return;
+  state.sessionList.pendingAction = "create";
+  renderSessionSidebar();
+  try {
+    const response = await fetchJson(`/v1/workbench/workspace/${encodeURIComponent(state.workspaceId)}/select-conversation`, {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      timeoutMs: Math.min(API_TIMEOUT_MS, 8000),
+      timeoutName: "Code Agent session create",
+      body: JSON.stringify({ projectId: WORKBENCH_PROJECT_ID, create: true, updatedByClient: "cloud-web" })
+    });
+    if (!response.ok) throw new Error(response.error || "session create failed");
+    applyWorkbenchWorkspace(response.data?.workspace);
+    applyConversationToActiveSession(response.data?.workspace?.selectedConversation, { clearWhenMissing: true });
+    clearCodeAgentSessionState();
+    await loadSessionSidebar({ quiet: true });
+    renderAgentChatStatus("idle");
+    renderCodeAgentSummary();
+    renderConversation();
+    renderDrafts();
+  } catch (error) {
+    state.sessionList.error = error?.message || String(error);
+    renderSessionSidebar();
+  } finally {
+    state.sessionList.pendingAction = null;
+    renderSessionSidebar();
+  }
+}
+
+async function selectSessionSidebarSession(tab) {
+  if (!tab?.conversationId || tab.conversationId === state.conversationId) return;
+  if (!(await ensureWorkbenchWorkspace())) return;
+  state.sessionList.pendingAction = "switch";
+  renderSessionSidebar();
+  try {
+    const response = await fetchJson(`/v1/workbench/workspace/${encodeURIComponent(state.workspaceId)}/select-conversation`, {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      timeoutMs: Math.min(API_TIMEOUT_MS, 8000),
+      timeoutName: "Code Agent session switch",
+      body: JSON.stringify({
+        projectId: WORKBENCH_PROJECT_ID,
+        conversationId: tab.conversationId,
+        sessionId: tab.sessionId,
+        threadId: tab.threadId,
+        updatedByClient: "cloud-web"
+      })
+    });
+    if (!response.ok) throw new Error(response.error || "session switch failed");
+    applyWorkbenchWorkspace(response.data?.workspace);
+    applyConversationToActiveSession(response.data?.workspace?.selectedConversation, { clearWhenMissing: true });
+    state.conversationScrollPosition = { top: 0, left: 0, bottomGap: 0 };
+    persistCodeAgentSessionState();
+    renderAgentChatStatus(latestChatResult()?.status ?? "idle", latestChatResult());
+    renderCodeAgentSummary();
+    renderConversation();
+    renderDrafts();
+  } catch (error) {
+    state.sessionList.error = error?.message || String(error);
+    renderSessionSidebar();
+  } finally {
+    state.sessionList.pendingAction = null;
+    renderSessionSidebar();
+  }
+}
+
+async function deleteCurrentSessionSidebarSession() {
+  const conversationId = state.conversationId;
+  if (!conversationId) return;
+  if (!window.confirm("删除当前 session？历史 trace 仍会保留在后端审计记录中。")) return;
+  state.sessionList.pendingAction = "delete";
+  renderSessionSidebar();
+  try {
+    const response = await fetchJson(`/v1/agent/conversations/${encodeURIComponent(conversationId)}`, {
+      method: "DELETE",
+      headers: { "Content-Type": "application/json" },
+      timeoutMs: Math.min(API_TIMEOUT_MS, 8000),
+      timeoutName: "Code Agent session delete",
+      body: JSON.stringify({ projectId: WORKBENCH_PROJECT_ID, workspaceId: state.workspaceId, updatedByClient: "cloud-web" })
+    });
+    if (!response.ok) throw new Error(response.error || "session delete failed");
+    if (response.data?.workspace) applyWorkbenchWorkspace(response.data.workspace);
+    applyConversationToActiveSession(response.data?.workspace?.selectedConversation, { clearWhenMissing: true });
+    clearCodeAgentSessionState();
+    await loadSessionSidebar({ quiet: true });
+    renderAgentChatStatus(latestChatResult()?.status ?? "idle", latestChatResult());
+    renderCodeAgentSummary();
+    renderConversation();
+    renderDrafts();
+  } catch (error) {
+    state.sessionList.error = error?.message || String(error);
+    renderSessionSidebar();
+  } finally {
+    state.sessionList.pendingAction = null;
+    renderSessionSidebar();
+  }
+}
+
+function applyConversationToActiveSession(conversation, options = {}) {
+  const payload = accountConversationToStoredSessionPayload(conversation);
+  if (!payload) {
+    if (options.clearWhenMissing === true) clearActiveConversationState();
+    return false;
+  }
+  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)
+    : [];
+  state.activeTraceId = activeTraceIdFromStoredMessages(state.chatMessages);
+  state.currentRequest = null;
+  state.chatPending = false;
+  return true;
+}
+
+function clearActiveConversationState() {
+  state.conversationId = null;
+  state.sessionId = null;
+  state.threadId = null;
+  state.activeTraceId = null;
+  state.sessionStatus = null;
+  state.chatMessages = [];
+  state.currentRequest = null;
+  state.chatPending = false;
+}
+
 function workspaceToStoredSessionPayload(workspace) {
   if (!workspace || typeof workspace !== "object") return null;
   const workspaceJson = workspace.workspace && typeof workspace.workspace === "object" ? workspace.workspace : {};

web/hwlab-cloud-web/index.html

@@ -62,6 +62,21 @@
         title="拖拽调整左侧导航宽度；用左右方向键微调，Home/End 到最小或最大。"
       ></div>
 
+      <aside class="session-sidebar" id="session-sidebar" aria-label="Code Agent sessions">
+        <header class="session-sidebar-head">
+          <div>
+            <p class="eyebrow">Sessions</p>
+            <h2>Agent Sessions</h2>
+          </div>
+          <button class="session-icon-button" id="session-create" type="button" aria-label="创建 session" title="创建 session">+</button>
+        </header>
+        <div class="session-tabs" id="session-tabs" role="tablist" aria-label="Code Agent sessions"></div>
+        <div class="session-sidebar-foot">
+          <span class="session-status" id="session-status">等待 workspace</span>
+          <button class="session-delete-button" id="session-delete" type="button" disabled>删除当前</button>
+        </div>
+      </aside>
+
       <section class="center-workspace">
         <section class="view workbench-view" id="workspace" data-view="workspace" aria-labelledby="workspace-title">
           <div class="conversation-column">

web/hwlab-cloud-web/scripts/check.ts

@@ -67,6 +67,7 @@ console.log("hwlab-cloud-web check: right sidebar extracted");
 assert.ok(rightSidebar, "Device Pod right sidebar must exist");
 assert.match(html, /data-route="skills"/u, "Cloud Web must expose the skills activity route");
 assert.match(html, /id="session-tabs"[^>]*role="tablist"/u, "Cloud Web workspace must expose session tabs");
+assert.match(html, /class="session-sidebar"[^>]*id="session-sidebar"/u, "Cloud Web must place sessions in a second-level sidebar");
 assert.match(html, /id="skills"[^>]*data-view="skills"/u, "Cloud Web must expose a skills view");
 assert.match(html, /id="skill-upload-input"[^>]*webkitdirectory/u, "Skills view must support directory upload");
 assertIncludes(app, "/v1/skills", "skills frontend must call /v1/skills");
@@ -82,9 +83,19 @@ assertIncludes(styles, ".skill-prompt-assembly", "skills frontend must style pro
 assertIncludes(styles, ".skill-prompt-row", "skills frontend must style prompt assembly refs");
 assertIncludes(app, "sessionTabsFromMessages", "workspace frontend must group messages by session");
 assertIncludes(app, "activeSessionKey", "workspace frontend must track the active session tab");
-assertIncludes(app, "currentSessionView", "workspace frontend must filter conversation rendering by selected session");
+assertIncludes(app, "renderSessionSidebar", "workspace frontend must render account-scoped sessions in the second-level sidebar");
+assertIncludes(app, "selectSessionSidebarSession", "workspace frontend must switch sessions from the second-level sidebar");
 assertIncludes(styles, ".session-tabs", "workspace frontend must style session tabs");
 assertIncludes(styles, ".session-tab", "workspace frontend must style individual session tabs");
+assertIncludes(app, "sessionTabsFromConversations", "workspace frontend must build session tabs from account conversations");
+assertIncludes(app, "/v1/agent/conversations", "workspace frontend must load account-scoped sessions");
+assertIncludes(app, "select-conversation", "workspace frontend must switch sessions through workbench select-conversation");
+assertIncludes(styles, ".session-sidebar", "workspace frontend must style the second-level session sidebar");
+assertIncludes(styles, "grid-template-columns: var(--rail-width) var(--session-sidebar-width)", "workspace shell must place session sidebar to the right of activity rail");
+assert.match(cssRule(styles, ".activity-rail"), /overflow-x:\s*hidden;/u, "activity rail must not horizontally scroll");
+assert.match(cssRule(styles, ".session-tabs"), /overflow-x:\s*hidden;/u, "session sidebar must not horizontally scroll");
+assert.match(cssRule(styles, ".rail-button"), /white-space:\s*nowrap;/u, "activity rail labels must not auto-wrap");
+assert.match(cssRule(styles, ".session-tab-label"), /white-space:\s*nowrap;/u, "session labels must not auto-wrap");
 console.log("hwlab-cloud-web check: skills contracts verified");
 
 for (const term of [

web/hwlab-cloud-web/scripts/dist-contract.ts

@@ -10,6 +10,7 @@ export const cloudWebDistFreshnessCommand = cloudWebDistBuildCommand;
 export const cloudWebAppSourceFiles = Object.freeze([
   "app.ts",
   "app-skills.ts",
+  "app-session-tabs.ts",
   "app-device-pod.ts",
   "app-conversation.ts",
   "app-trace.ts",

web/hwlab-cloud-web/session-tabs.test.ts

@@ -1,7 +1,7 @@
 import assert from "node:assert/strict";
 import test from "node:test";
 
-import { activeSessionKeyFromRuntime, sessionTabsFromMessages } from "./app-session-tabs.ts";
+import { activeSessionKeyFromRuntime, sessionTabsFromConversations, sessionTabsFromMessages } from "./app-session-tabs.ts";
 
 test("session tabs group messages and filter the active session", () => {
   const messages = [
@@ -55,6 +55,28 @@ test("runtime active session prefers current request session before global state
   assert.equal(key, "ses_current");
 });
 
+test("session tabs use account conversations and keep the selected session active", () => {
+  const view = sessionTabsFromConversations([
+    conversation("cnv_old", "ses_old", "trc_old", "idle", "2026-06-03T00:00:01Z"),
+    conversation("cnv_new", "ses_new", "trc_new", "running", "2026-06-03T00:00:03Z")
+  ], { selectedConversationId: "cnv_old" });
+
+  assert.equal(view.tabs.length, 2);
+  assert.equal(view.activeConversation?.conversationId, "cnv_old");
+  assert.equal(view.tabs[0].conversationId, "cnv_new");
+  assert.equal(view.tabs.find((tab) => tab.conversationId === "cnv_new")?.subtitle, "处理中");
+});
+
+test("session tabs default to newest visible conversation", () => {
+  const view = sessionTabsFromConversations([
+    conversation("cnv_a", "ses_a", "trc_a", "idle", "2026-06-03T00:00:01Z"),
+    conversation("cnv_b", "ses_b", "trc_b", "completed", "2026-06-03T00:00:05Z")
+  ], { selectedConversationId: "missing" });
+
+  assert.equal(view.activeConversation?.conversationId, "cnv_b");
+  assert.equal(view.activeKey, "ses_b");
+});
+
 function message(role, sessionId, conversationId, traceId, status, createdAt) {
   return {
     id: `${role}_${traceId}`,
@@ -68,3 +90,14 @@ function message(role, sessionId, conversationId, traceId, status, createdAt) {
     createdAt
   };
 }
+
+function conversation(conversationId, sessionId, traceId, status, updatedAt) {
+  return {
+    conversationId,
+    sessionId,
+    status,
+    updatedAt,
+    lastTraceId: traceId,
+    messages: [{ role: "agent", text: traceId, status, traceId, updatedAt }]
+  };
+}

web/hwlab-cloud-web/styles.css

@@ -89,6 +89,7 @@ ul {
 
 .workbench-shell {
   --rail-width: clamp(var(--left-sidebar-min-width), var(--left-sidebar-width), var(--left-sidebar-max-width));
+  --session-sidebar-width: clamp(174px, 17vw, 236px);
   --right-width: clamp(var(--right-sidebar-min-width), var(--right-sidebar-width), var(--right-sidebar-max-width));
   --right-width-expanded: clamp(var(--right-sidebar-min-width), var(--right-sidebar-width), var(--right-sidebar-max-width));
   position: relative;
@@ -97,7 +98,7 @@ ul {
   max-height: 100dvh;
   min-height: 0;
   display: grid;
-  grid-template-columns: var(--rail-width) minmax(420px, 1fr) var(--right-width-expanded);
+  grid-template-columns: var(--rail-width) var(--session-sidebar-width) minmax(420px, 1fr) var(--right-width-expanded);
   grid-template-rows: 1fr;
   overflow: hidden;
   overscroll-behavior: contain;
@@ -239,6 +240,7 @@ body > [data-app-shell][hidden] {
 }
 
 .activity-rail,
+.session-sidebar,
 .right-sidebar,
 .center-workspace {
   min-width: 0;
@@ -252,7 +254,157 @@ body > [data-app-shell][hidden] {
   padding: 8px;
   background: var(--rail);
   border-right: 1px solid var(--line);
-  overflow: auto;
+  overflow-x: hidden;
+  overflow-y: auto;
+}
+
+.session-sidebar {
+  display: grid;
+  grid-template-rows: auto minmax(0, 1fr) auto;
+  gap: 8px;
+  padding: 8px;
+  background: rgba(19, 22, 20, 0.98);
+  border-right: 1px solid var(--line);
+  overflow: hidden;
+  overscroll-behavior: contain;
+}
+
+.session-sidebar-head {
+  min-width: 0;
+  display: grid;
+  grid-template-columns: minmax(0, 1fr) auto;
+  gap: 8px;
+  align-items: center;
+  padding: 6px 6px 8px;
+  border-bottom: 1px solid var(--line);
+}
+
+.session-sidebar-head h2 {
+  font-size: 13px;
+  line-height: 1.2;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.session-icon-button {
+  width: 30px;
+  height: 30px;
+  border: 1px solid var(--line-strong);
+  background: var(--surface-2);
+  color: var(--text);
+  font-size: 18px;
+  font-weight: 760;
+  line-height: 1;
+  cursor: pointer;
+}
+
+.session-icon-button:hover,
+.session-icon-button:focus-visible,
+.session-delete-button:hover,
+.session-delete-button:focus-visible {
+  border-color: var(--accent);
+  outline: 0;
+}
+
+.session-tabs {
+  min-width: 0;
+  min-height: 0;
+  display: grid;
+  align-content: start;
+  gap: 6px;
+  overflow-x: hidden;
+  overflow-y: auto;
+  scrollbar-gutter: stable;
+}
+
+.session-tab {
+  width: 100%;
+  min-width: 0;
+  display: grid;
+  grid-template-columns: minmax(0, 1fr) auto;
+  gap: 2px 8px;
+  align-items: center;
+  padding: 8px;
+  border: 1px solid var(--line);
+  border-left-width: 3px;
+  background: rgba(16, 19, 17, 0.86);
+  color: var(--muted);
+  text-align: left;
+  cursor: pointer;
+}
+
+.session-tab[aria-selected="true"] {
+  background: rgba(31, 39, 34, 0.94);
+  border-color: var(--line-strong);
+  color: var(--text);
+}
+
+.session-tab:hover,
+.session-tab:focus-visible {
+  border-color: var(--accent);
+  outline: 0;
+}
+
+.session-tab-label,
+.session-tab-subtitle,
+.session-tab-count,
+.session-status {
+  min-width: 0;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.session-tab-label {
+  color: var(--text);
+  font-size: 12px;
+  font-weight: 760;
+  white-space: nowrap;
+}
+
+.session-tab-subtitle {
+  color: var(--dim);
+  font-family: var(--mono);
+  font-size: 10px;
+}
+
+.session-tab-count {
+  grid-row: span 2;
+  color: var(--accent);
+  font-family: var(--mono);
+  font-size: 10px;
+}
+
+.session-sidebar-foot {
+  min-width: 0;
+  display: grid;
+  gap: 6px;
+  padding-top: 8px;
+  border-top: 1px solid var(--line);
+}
+
+.session-status {
+  color: var(--muted);
+  font-family: var(--mono);
+  font-size: 10px;
+}
+
+.session-delete-button {
+  min-width: 0;
+  min-height: 32px;
+  border: 1px solid var(--line-strong);
+  background: var(--surface-2);
+  color: var(--text);
+  font-size: 11px;
+  font-weight: 760;
+  cursor: pointer;
+}
+
+.session-delete-button:disabled,
+.session-icon-button:disabled {
+  cursor: progress;
+  opacity: 0.58;
 }
 
 .rail-spacer {
@@ -272,7 +424,10 @@ body > [data-app-shell][hidden] {
   line-height: 1.2;
   cursor: pointer;
   text-align: center;
-  overflow-wrap: anywhere;
+  overflow: hidden;
+  overflow-wrap: normal;
+  text-overflow: ellipsis;
+  white-space: nowrap;
   word-break: keep-all;
 }
 
@@ -2352,12 +2507,13 @@ tbody tr:last-child td {
 @media (max-width: 1240px) {
   .workbench-shell {
     --rail-width: 86px;
-    grid-template-columns: var(--rail-width) minmax(0, 1fr);
+    --session-sidebar-width: clamp(158px, 22vw, 204px);
+    grid-template-columns: var(--rail-width) var(--session-sidebar-width) minmax(0, 1fr);
     grid-template-rows: minmax(0, 1fr) clamp(220px, 36dvh, 360px);
   }
 
   .right-sidebar {
-    grid-column: 2;
+    grid-column: 2 / 4;
     grid-row: 2;
     min-height: 0;
     padding-left: 10px;
@@ -2374,7 +2530,8 @@ tbody tr:last-child td {
 @media (max-width: 860px) {
   .workbench-shell {
     --rail-width: 68px;
-    grid-template-columns: var(--rail-width) minmax(0, 1fr);
+    --session-sidebar-width: 148px;
+    grid-template-columns: var(--rail-width) var(--session-sidebar-width) minmax(0, 1fr);
     grid-template-rows: minmax(0, 1fr) clamp(214px, 30dvh, 280px);
   }
 
@@ -2401,7 +2558,25 @@ tbody tr:last-child td {
 
   .center-workspace,
   .right-sidebar {
+    grid-column: 3;
+  }
+
+  .session-sidebar {
     grid-column: 2;
+    grid-row: 1 / 3;
+    padding: 7px;
+  }
+
+  .session-sidebar-head {
+    padding: 5px 4px 7px;
+  }
+
+  .session-sidebar-head h2 {
+    font-size: 12px;
+  }
+
+  .session-tab {
+    padding: 7px 6px;
   }
 
   .center-workspace {
@@ -2551,7 +2726,8 @@ tbody tr:last-child td {
 @media (max-width: 520px) {
   .workbench-shell {
     --rail-width: 64px;
-    grid-template-columns: var(--rail-width) minmax(0, 1fr);
+    --session-sidebar-width: 128px;
+    grid-template-columns: var(--rail-width) var(--session-sidebar-width) minmax(0, 1fr);
     grid-template-rows: minmax(0, 1fr) clamp(260px, 34dvh, 320px);
   }