diff --git a/scripts/pi-bridge.test.mjs b/scripts/pi-bridge.test.mjs
new file mode 100644
index 0000000..cac909e
--- /dev/null
+++ b/scripts/pi-bridge.test.mjs
@@ -0,0 +1,122 @@
+/**
+ * 能力桥用例（任务 A3.4 / A3.11）。
+ *
+ * 不启动 Pi：把扩展装到一个假的 Pi 注册表上，直接调它注册出来的工具，
+ * 验证「Pi 工具调用 → 平台内部端点 → Core.invoke → 假 Provider → 回执」这条链路。
+ * 真引擎那一环另有一条需要 APS_PI_INTEGRATION=1 的用例（见 pi-runtime.test.mjs）。
+ */
+import assert from 'node:assert/strict';
+import { mkdtemp, rm, writeFile } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { test } from 'node:test';
+import { pathToFileURL } from 'node:url';
+
+const EXTENSION = pathToFileURL(join(process.cwd(), 'server/agent/pi/extension/aps-bridge.ts')).href;
+
+async function startPlatform() {
+  process.env.APS_DEV_PROVIDER = '1';
+  const { startServer } = await import('../server/dist/index.js');
+  return startServer({ host: '127.0.0.1', port: 0, version: 'test', databasePath: ':memory:', engine: 'fake' });
+}
+
+/** 用假 Pi 加载扩展，返回注册出来的工具表 */
+async function loadBridge(configPath) {
+  const previous = process.env.APS_BRIDGE_CONFIG;
+  process.env.APS_BRIDGE_CONFIG = configPath;
+  try {
+    const module = await import(EXTENSION);
+    const tools = new Map();
+    module.default({
+      registerTool(tool) {
+        tools.set(tool.name, tool);
+      },
+    });
+    return tools;
+  } finally {
+    if (previous === undefined) delete process.env.APS_BRIDGE_CONFIG;
+    else process.env.APS_BRIDGE_CONFIG = previous;
+  }
+}
+
+async function writeBridgeConfig(server, sessionId, capabilities) {
+  const dir = await mkdtemp(join(tmpdir(), 'aps-bridge-'));
+  const file = join(dir, 'bridge.json');
+  await writeFile(
+    file,
+    JSON.stringify({ baseUrl: server.url, internalToken: server.internalToken, sessionId, capabilities }),
+    'utf8',
+  );
+  return { dir, file };
+}
+
+test('扩展把平台能力注册成 Pi 工具，调用经 Core.invoke 返回回执', async () => {
+  const server = await startPlatform();
+  const created = await (
+    await fetch(`${server.url}/v1/sessions`, {
+      method: 'POST',
+      headers: { 'content-type': 'application/json' },
+      body: JSON.stringify({ scope: 'project', projectId: 'p-default', title: '桥用例' }),
+    })
+  ).json();
+  const sessionId = created.session.sessionId;
+
+  const { dir, file } = await writeBridgeConfig(server, sessionId, [
+    {
+      toolName: 'fake_echo',
+      capabilityId: 'fake.echo',
+      description: '回显输入',
+      parameters: { type: 'object', properties: { text: { type: 'string' } }, required: ['text'] },
+    },
+  ]);
+
+  try {
+    const tools = await loadBridge(file);
+    assert.ok(tools.has('fake_echo'), `应注册 fake_echo，实际：${[...tools.keys()].join(',')}`);
+
+    const tool = tools.get('fake_echo');
+    const result = await tool.execute('call-abc', { text: '你好' });
+    const receipt = JSON.parse(result.content[0].text);
+    assert.equal(receipt.status, 'succeeded');
+    assert.deepEqual(receipt.result, { echo: '你好' });
+
+    // 平台侧留下执行记录，且能经 HTTP 查到
+    const execution = await (await fetch(`${server.url}/v1/executions/${receipt.executionId}`)).json();
+    assert.equal(execution.status, 'succeeded');
+    const record = server.service.core.executions.get(receipt.executionId);
+    assert.equal(record.sessionId, sessionId, '执行记录应归属发起会话');
+    assert.equal(record.capabilityId, 'fake.echo');
+  } finally {
+    await server.close();
+    await rm(dir, { recursive: true, force: true });
+    delete process.env.APS_DEV_PROVIDER;
+  }
+});
+
+test('能力不存在时扩展抛错，Pi 会把它当工具错误（不会伪造成功）', async () => {
+  const server = await startPlatform();
+  const created = await (
+    await fetch(`${server.url}/v1/sessions`, {
+      method: 'POST',
+      headers: { 'content-type': 'application/json' },
+      body: JSON.stringify({ scope: 'project', projectId: 'p-default', title: '失败路径' }),
+    })
+  ).json();
+  const { dir, file } = await writeBridgeConfig(server, created.session.sessionId, [
+    { toolName: 'fake_nope', capabilityId: 'fake.__nope__', description: '不存在的能力', parameters: { type: 'object' } },
+  ]);
+
+  try {
+    const tools = await loadBridge(file);
+    await assert.rejects(() => tools.get('fake_nope').execute('call-bad', {}), /执行失败|invalid_argument/);
+  } finally {
+    await server.close();
+    await rm(dir, { recursive: true, force: true });
+    delete process.env.APS_DEV_PROVIDER;
+  }
+});
+
+test('没有桥配置时不注册任何工具（宁可说做不到，也不给坏工具）', async () => {
+  const tools = await loadBridge(join(tmpdir(), 'not-exists-bridge.json'));
+  assert.equal(tools.size, 0);
+});
\ No newline at end of file
diff --git a/scripts/turn-runner.test.mjs b/scripts/turn-runner.test.mjs
new file mode 100644
index 0000000..e015dba
--- /dev/null
+++ b/scripts/turn-runner.test.mjs
@@ -0,0 +1,106 @@
+/**
+ * 回合执行器按工具执行模式分流（A3.4）。
+ *
+ * 两种模式必须都覆盖，否则 Pi 那条路只有真模型测试才碰得到：
+ *   platform —— 平台执行并回填（假引擎走这条）
+ *   runtime  —— 引擎自己执行（Pi + 扩展桥），平台只观察事件、不得重复执行
+ */
+import assert from 'node:assert/strict';
+import { test } from 'node:test';
+
+import { runTurn } from '@aps/server/app/turn-runner';
+
+function stubSession(mode, events) {
+  return {
+    id: 'stub',
+    toolExecution: mode,
+    async *send() {
+      for (const event of events) yield event;
+    },
+    resolveToolResult() {},
+    abort() {},
+    async dispose() {},
+  };
+}
+
+const toolCallEvents = [
+  { type: 'text', delta: '我来调用。' },
+  { type: 'tool_call', callId: 'c-1', capabilityId: 'test.echo', args: { q: 1 } },
+  { type: 'tool_result', callId: 'c-1', receipt: { executionId: 'exec-1', status: 'succeeded' } },
+  { type: 'turn_end', reason: 'stop' },
+];
+
+function collect() {
+  const events = [];
+  return { events, publish: (event) => events.push(event) };
+}
+
+test('runtime 模式：平台不执行工具，只观察 tool.call 与 tool.result', async () => {
+  const { events, publish } = collect();
+  let invocations = 0;
+  const result = await runTurn({
+    runtimeSession: stubSession('runtime', toolCallEvents),
+    sessionId: 's-1',
+    runId: 'r-1',
+    assistantMessageId: 'm-1',
+    text: '调用试试',
+    publish,
+    invoke: async () => {
+      invocations += 1;
+      return { executionId: 'platform-should-not-run', status: 'succeeded' };
+    },
+    signal: new AbortController().signal,
+  });
+
+  assert.equal(invocations, 0, '引擎模式下平台不得再执行一次（否则等于重复调用）');
+  const types = events.map((event) => event.type);
+  assert.deepEqual(types, ['run.state', 'message.delta', 'tool.call', 'tool.result', 'message.completed', 'run.state']);
+  assert.equal(result.toolCalls, 1);
+  assert.equal(result.finishReason, 'stop');
+});
+
+test('platform 模式：平台执行并把回执回填给运行时', async () => {
+  const { events, publish } = collect();
+  const resolved = [];
+  const session = stubSession('platform', toolCallEvents);
+  session.resolveToolResult = (callId, receipt) => resolved.push({ callId, receipt });
+
+  let invocations = 0;
+  await runTurn({
+    runtimeSession: session,
+    sessionId: 's-1',
+    runId: 'r-1',
+    assistantMessageId: 'm-1',
+    text: '调用试试',
+    publish,
+    invoke: async () => {
+      invocations += 1;
+      return { executionId: 'exec-platform', status: 'succeeded' };
+    },
+    signal: new AbortController().signal,
+  });
+
+  assert.equal(invocations, 1, '平台模式必须执行一次');
+  assert.deepEqual(resolved, [{ callId: 'c-1', receipt: { executionId: 'exec-platform', status: 'succeeded' } }]);
+  const types = events.map((event) => event.type);
+  assert.ok(types.includes('tool.result'), types.join(','));
+});
+
+test('错误回合的结束原因不会被 turn_end 覆盖回 stop', async () => {
+  const { events, publish } = collect();
+  const result = await runTurn({
+    runtimeSession: stubSession('runtime', [
+      { type: 'error', kind: 'forbidden', message: '401 无效密钥' },
+      { type: 'turn_end', reason: 'stop' },
+    ]),
+    sessionId: 's-1',
+    runId: 'r-1',
+    assistantMessageId: 'm-1',
+    text: '触发错误',
+    publish,
+    invoke: async () => ({ executionId: 'x', status: 'succeeded' }),
+    signal: new AbortController().signal,
+  });
+  assert.equal(result.finishReason, 'error');
+  assert.equal(events.find((event) => event.type === 'message.completed').data.finishReason, 'error');
+});
\ No newline at end of file
diff --git a/server/agent/fake-runtime.ts b/server/agent/fake-runtime.ts
index 9c825f8..6e904eb 100644
--- a/server/agent/fake-runtime.ts
+++ b/server/agent/fake-runtime.ts
@@ -41,6 +41,7 @@ export function createFakeRuntime(options: FakeRuntimeOptions = {}): FakeRuntime
 
   return {
     name: options.name ?? 'fake',
+    toolExecution: 'platform',
     stats,
     async createSession(input: CreateRuntimeSessionInput): Promise<RuntimeSession> {
       stats.sessions += 1;
@@ -115,6 +116,7 @@ export function createFakeRuntime(options: FakeRuntimeOptions = {}): FakeRuntime
 
       return {
         id,
+        toolExecution: 'platform',
         send(text: string, sendOptions?: SendOptions): AsyncIterable<RuntimeEvent> {
           return runTurn(text, sendOptions);
         },
diff --git a/server/agent/pi/extension/aps-bridge.ts b/server/agent/pi/extension/aps-bridge.ts
new file mode 100644
index 0000000..77f58d5
--- /dev/null
+++ b/server/agent/pi/extension/aps-bridge.ts
@@ -0,0 +1,91 @@
+/**
+ * 平台能力桥（任务 A3.11）：把平台的能力目录注册成 Pi 的工具。
+ *
+ * 这个文件由平台以 `--extension <path>` 加载，运行在 Pi 子进程里（Pi 用 jiti 直接读 TS）。
+ * 它自己不判断权限、不碰凭据，只做一件事：把 Pi 的工具调用转成对平台内部回调端点的 HTTP 请求，
+ * 平台侧收口到 Core.invoke（架构设计 5.1「每次都过 Core」）。
+ *
+ * 配置来自环境变量 APS_BRIDGE_CONFIG 指向的 JSON 文件，由平台在建立会话时写入：
+ *   { baseUrl, internalToken, sessionId, capabilities: [{ toolName, capabilityId, description, parameters }] }
+ */
+import { readFileSync } from 'node:fs';
+
+interface BridgeCapability {
+  toolName: string;
+  capabilityId: string;
+  description: string;
+  parameters: Record<string, unknown>;
+}
+
+interface BridgeConfig {
+  baseUrl: string;
+  internalToken: string;
+  sessionId: string;
+  capabilities: BridgeCapability[];
+}
+
+interface PlatformReceipt {
+  executionId: string;
+  status: 'accepted' | 'pending-confirmation' | 'succeeded' | 'failed';
+  result?: unknown;
+  errorKind?: string;
+}
+
+/** Pi 扩展的注册接口（只声明用到的部分，避免扩展依赖 Pi 的类型包） */
+interface PiExtensionApi {
+  registerTool(tool: {
+    name: string;
+    label: string;
+    description: string;
+    parameters: Record<string, unknown>;
+    execute: (toolCallId: string, params: unknown, signal?: AbortSignal) => Promise<{ content: Array<{ type: 'text'; text: string }>; details: unknown }>;
+  }): void;
+}
+
+export default function apsBridge(pi: PiExtensionApi): void {
+  const configPath = process.env.APS_BRIDGE_CONFIG ?? '';
+  if (configPath === '') return;
+
+  let config: BridgeConfig;
+  try {
+    config = JSON.parse(readFileSync(configPath, 'utf8')) as BridgeConfig;
+  } catch {
+    // 配置读不到就不注册任何工具：宁可让模型说做不到，也不要注册一个坏工具
+    return;
+  }
+
+  for (const capability of config.capabilities) {
+    pi.registerTool({
+      name: capability.toolName,
+      label: capability.capabilityId,
+      description: capability.description,
+      parameters: capability.parameters,
+      async execute(toolCallId: string, params: unknown, signal?: AbortSignal) {
+        const response = await fetch(`${config.baseUrl}/internal/tool-call`, {
+          method: 'POST',
+          headers: { 'content-type': 'application/json', 'x-aps-internal-token': config.internalToken },
+          body: JSON.stringify({
+            sessionId: config.sessionId,
+            capabilityId: capability.capabilityId,
+            params,
+            idempotencyKey: `call-${toolCallId}`,
+          }),
+          ...(signal === undefined ? {} : { signal }),
+        });
+
+        if (!response.ok) {
+          const detail = await response.text().catch(() => '');
+          throw new Error(`平台拒绝调用（HTTP ${response.status}）：${detail.slice(0, 200)}`);
+        }
+
+        const receipt = (await response.json()) as PlatformReceipt;
+        if (receipt.status === 'failed') {
+          const detail = (receipt.result as { message?: string } | undefined)?.message ?? '未提供原因';
+          throw new Error(`能力 ${capability.capabilityId} 执行失败（${receipt.errorKind ?? 'unknown'}）：${detail}`);
+        }
+        // 成功：把回执原样交给模型（含 executionId，便于它引用证据）
+        return { content: [{ type: 'text', text: JSON.stringify(receipt) }], details: receipt };
+      },
+    });
+  }
+}
\ No newline at end of file
diff --git a/server/agent/pi/runtime.ts b/server/agent/pi/runtime.ts
index 0fa8a26..7afc4dc 100644
--- a/server/agent/pi/runtime.ts
+++ b/server/agent/pi/runtime.ts
@@ -7,7 +7,7 @@
  * - 事件面：把 Pi 的会话事件映射成平台的 RuntimeEvent，上层只认平台类型
  * - 状态：平台保存会话历史；Pi 自己的 session 文件放在平台管理目录里，只作同引擎恢复用（ADR-0003）
  */
-import { existsSync } from 'node:fs';
+import { existsSync, mkdirSync, writeFileSync } from 'node:fs';
 import { homedir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -29,6 +29,16 @@ export interface PiRuntimeOptions {
   extraArgs?: string[];
   /** 单回合最长等待（毫秒），超时按引擎错误处理 */
   turnTimeoutMs?: number;
+  /**
+   * 能力桥：给定平台内部回调地址与令牌。
+   * 传了它就会加载平台的能力桥扩展，Pi 才真正拥有平台的能力目录（A3.11）。
+   * 用函数是为了延后取值——端口要等监听之后才知道。
+   */
+  bridge?: () => { baseUrl: string; internalToken: string } | undefined;
+  /** 能力桥扩展文件路径（默认取仓库里的 server/agent/pi/extension/aps-bridge.ts） */
+  extensionPath?: string;
+  /** 桥配置文件目录（默认 ~/.aps/pi-bridge，内含内部令牌，不入库） */
+  bridgeDir?: string;
 }
 
 /** provider → 环境变量名：密钥走环境，不进命令行（命令行会被进程列表看到） */
@@ -124,14 +134,22 @@ export function mapPiEvent(event: JsonAgentSessionEvent): RuntimeEvent[] {
   }
 }
 
+/** 默认扩展路径：从编译产物反推仓库里的源文件（Pi 用 jiti 直接读 TS） */
+function defaultExtensionPath(): string {
+  return fileURLToPath(new URL('../../../agent/pi/extension/aps-bridge.ts', import.meta.url));
+}
+
 export function createPiRuntime(options: PiRuntimeOptions = {}): AgentRuntime {
   const provider = options.provider ?? 'deepseek';
   const model = options.model ?? 'deepseek-chat';
   const sessionDir = options.sessionDir ?? join(homedir(), '.aps', 'pi-sessions');
+  const bridgeDir = options.bridgeDir ?? join(homedir(), '.aps', 'pi-bridge');
   const turnTimeoutMs = options.turnTimeoutMs ?? DEFAULT_TURN_TIMEOUT_MS;
 
   return {
     name: `pi:${provider}/${model}`,
+    // 工具在 Pi 子进程里执行（经扩展桥回调平台的内部端点），平台只观察事件
+    toolExecution: 'runtime',
     async createSession(input: CreateRuntimeSessionInput): Promise<RuntimeSession> {
       const env: Record<string, string> = {};
       for (const [key, value] of Object.entries(process.env)) {
@@ -141,6 +159,26 @@ export function createPiRuntime(options: PiRuntimeOptions = {}): AgentRuntime {
         env[API_KEY_ENV[provider] ?? 'DEEPSEEK_API_KEY'] = options.apiKey;
       }
 
+      // 能力桥：写一份会话专属配置给扩展读（含内部令牌，放用户目录、不入库）
+      const bridge = options.bridge?.();
+      if (bridge) {
+        mkdirSync(bridgeDir, { recursive: true });
+        const bridgeConfigPath = join(bridgeDir, `${input.sessionId}.json`);
+        const bridgeConfig = {
+          baseUrl: bridge.baseUrl,
+          internalToken: bridge.internalToken,
+          sessionId: input.sessionId,
+          capabilities: input.tools.map((tool) => ({
+            toolName: tool.toolName,
+            capabilityId: tool.capabilityId,
+            description: tool.description,
+            parameters: tool.parameters,
+          })),
+        };
+        writeFileSync(bridgeConfigPath, JSON.stringify(bridgeConfig, null, 2), { mode: 0o600 });
+        env.APS_BRIDGE_CONFIG = bridgeConfigPath;
+      }
+
       const cliPath = options.cliPath ?? defaultCliPath();
       const client = new RpcClient({
         ...(cliPath === '' ? {} : { cliPath }),
@@ -155,6 +193,9 @@ export function createPiRuntime(options: PiRuntimeOptions = {}): AgentRuntime {
           '--no-skills',
           '--no-prompt-templates',
           '--no-context-files',
+          // 只加载平台自己的能力桥扩展（--no-extensions 关掉自动发现，-e 显式加载仍然有效）
+          '-e',
+          options.extensionPath ?? defaultExtensionPath(),
           '--session-dir',
           sessionDir,
           '--session-id',
@@ -172,6 +213,7 @@ export function createPiRuntime(options: PiRuntimeOptions = {}): AgentRuntime {
 
       return {
         id: `pi-${input.sessionId}`,
+        toolExecution: 'runtime',
         async *send(text: string, sendOptions?: SendOptions): AsyncIterable<RuntimeEvent> {
           const queue: RuntimeEvent[] = [];
           let wake: (() => void) | undefined;
@@ -225,4 +267,4 @@ export function createPiRuntime(options: PiRuntimeOptions = {}): AgentRuntime {
       };
     },
   };
-}
\ No newline at end of file
+}
diff --git a/server/agent/runtime.ts b/server/agent/runtime.ts
index 5a7ab56..f94754f 100644
--- a/server/agent/runtime.ts
+++ b/server/agent/runtime.ts
@@ -77,6 +77,8 @@ export interface SendOptions {
 
 export interface RuntimeSession {
   readonly id: string;
+  /** 与运行时的 toolExecution 一致：决定工具由平台执行还是引擎自己执行 */
+  readonly toolExecution: 'platform' | 'runtime';
   /** 发一轮输入，产出事件流；流结束表示这一回合结束 */
   send(text: string, options?: SendOptions): AsyncIterable<RuntimeEvent>;
   /** 工具执行完回填回执，运行时据此继续生成后续事件 */
@@ -89,5 +91,11 @@ export interface RuntimeSession {
 
 export interface AgentRuntime {
   readonly name: string;
+  /**
+   * 工具由谁执行：
+   *   platform —— 运行时只发 tool_call，平台经 Core.invoke 执行后把回执送回来（假引擎走这条）
+   *   runtime  —— 工具在引擎子进程里执行（Pi 走扩展桥，扩展自己回调平台的内部端点）
+   */
+  readonly toolExecution: 'platform' | 'runtime';
   createSession(input: CreateRuntimeSessionInput): Promise<RuntimeSession>;
 }
\ No newline at end of file
diff --git a/server/app/turn-runner.ts b/server/app/turn-runner.ts
index 3365d7e..475573c 100644
--- a/server/app/turn-runner.ts
+++ b/server/app/turn-runner.ts
@@ -61,27 +61,30 @@ export async function runTurn(input: TurnRunnerInput): Promise<TurnResult> {
             type: 'tool.call',
             data: { callId: event.callId, capabilityId: event.capabilityId, argsDigest: digestParams(event.args) },
           });
-          // 幂等键用 callId：同一回合重放不会重复执行
-          const receipt = await invoke(event.capabilityId, event.args, `call-${event.callId}`);
-          publish({
-            sessionId,
-            runId,
-            type: 'tool.result',
-            data: { callId: event.callId, executionId: receipt.executionId, status: receipt.status },
-          });
-          runtimeSession.resolveToolResult(event.callId, receipt);
-          if (receipt.status === 'failed') {
-            publish({
-              sessionId,
-              runId,
-              type: 'error',
-              data: { code: `tool.${receipt.errorKind ?? 'failed'}`, message: toolFailureText(receipt), retryable: true },
-            });
+          // 平台模式：这里执行并回填；引擎模式（Pi + 扩展桥）由扩展自己回调平台执行，平台只观察
+          if (runtimeSession.toolExecution === 'platform') {
+            // 幂等键用 callId：同一回合重放不会重复执行
+            const receipt = await invoke(event.capabilityId, event.args, `call-${event.callId}`);
+            runtimeSession.resolveToolResult(event.callId, receipt);
+            if (receipt.status === 'failed') {
+              publish({
+                sessionId,
+                runId,
+                type: 'error',
+                data: { code: `tool.${receipt.errorKind ?? 'failed'}`, message: toolFailureText(receipt), retryable: true },
+              });
+            }
           }
           break;
         }
         case 'tool_result': {
-          // 运行时自行上报的回执（真引擎可能直接给），不重复发事件
+          // tool.result 只有这一个出处：运行时上报的回执（平台模式由假引擎回显，引擎模式由 Pi 上报）
+          publish({
+            sessionId,
+            runId,
+            type: 'tool.result',
+            data: { callId: event.callId, executionId: event.receipt.executionId, status: event.receipt.status },
+          });
           break;
         }
         case 'approval_required': {
diff --git a/server/index.ts b/server/index.ts
index 1e5495a..93ee556 100644
--- a/server/index.ts
+++ b/server/index.ts
@@ -43,7 +43,10 @@ export async function startServer(options: StartOptions = {}): Promise<RunningSe
   const config = loadConfig();
   const host = options.host ?? config.server.host;
   const port = options.port ?? config.server.port;
-  const runtime = options.runtime ?? (await selectRuntime(config, options.engine));
+  const internalToken = randomUUID();
+  // 端口要等 listen 之后才知道，所以桥信息用闭包延后取（A3.11 的能力桥需要它）
+  const bridgeRef: { info?: { baseUrl: string; internalToken: string } } = {};
+  const runtime = options.runtime ?? (await selectRuntime(config, options.engine, () => bridgeRef.info));
   const database: Database = openDatabase(options.databasePath ?? config.database.path);
   const service = new ApplicationService({
     ...(options.version === undefined ? {} : { version: options.version }),
@@ -56,7 +59,6 @@ export async function startServer(options: StartOptions = {}): Promise<RunningSe
     await service.registerProvider(createFakeProvider());
   }
 
-  const internalToken = randomUUID();
   const server: Server = createHttpServer(service, internalToken);
 
   await new Promise<void>((resolve, reject) => {
@@ -66,6 +68,8 @@ export async function startServer(options: StartOptions = {}): Promise<RunningSe
 
   const address = server.address() as AddressInfo | null;
   const actualPort = address ? address.port : port;
+  // 监听完成后才拿得到真实端口，这时桥信息才可用
+  bridgeRef.info = { baseUrl: `http://${host}:${actualPort}`, internalToken };
 
   return {
     url: `http://${host}:${actualPort}`,
@@ -83,7 +87,11 @@ export async function startServer(options: StartOptions = {}): Promise<RunningSe
   };
 }
 /** 引擎选择：显式注入 > 配置里的 engine.kind；选 pi 但没密钥时明确回退到假引擎 */
-async function selectRuntime(config: ReturnType<typeof loadConfig>, override?: 'fake' | 'pi'): Promise<AgentRuntime> {
+async function selectRuntime(
+  config: ReturnType<typeof loadConfig>,
+  override?: 'fake' | 'pi',
+  bridge?: () => { baseUrl: string; internalToken: string } | undefined,
+): Promise<AgentRuntime> {
   const kind = override ?? config.engine.kind;
   if (kind !== 'pi') {
     const { createFakeRuntime } = await import('./agent/fake-runtime.js');
@@ -97,5 +105,10 @@ async function selectRuntime(config: ReturnType<typeof loadConfig>, override?: '
     return createFakeRuntime({ name: 'fake', planner: plannerToFakeTurn(createRulePlanner()) });
   }
   const { createPiRuntime } = await import('./agent/pi/runtime.js');
-  return createPiRuntime({ provider: config.llm.provider, model: config.llm.model, apiKey: config.llm.apiKey });
-}
\ No newline at end of file
+  return createPiRuntime({
+    provider: config.llm.provider,
+    model: config.llm.model,
+    apiKey: config.llm.apiKey,
+    ...(bridge === undefined ? {} : { bridge }),
+  });
+}
diff --git a/server/package.json b/server/package.json
index b156414..036128f 100644
--- a/server/package.json
+++ b/server/package.json
@@ -10,6 +10,10 @@
       "types": "./dist/index.d.ts",
       "default": "./dist/index.js"
     },
+    "./app/turn-runner": {
+      "types": "./dist/app/turn-runner.d.ts",
+      "default": "./dist/app/turn-runner.js"
+    },
     "./config": {
       "types": "./dist/config.d.ts",
       "default": "./dist/config.js"