Fix misleading browser_close message by adding resultOverride

Co-authored-by: Skn0tt <14912729+Skn0tt@users.noreply.github.com>

README.md

@@ -52,6 +52,12 @@ After installation, the Playwright MCP server will be available for use with you
 <details>
 <summary><b>Install in Cursor</b></summary>
 
+#### Click the button to install:
+
+[![Install MCP Server](https://cursor.com/deeplink/mcp-install-dark.svg)](https://cursor.com/install-mcp?name=playwright&config=eyJjb21tYW5kIjoibnB4IEBwbGF5d3JpZ2h0L21jcEBsYXRlc3QifQ%3D%3D)
+
+#### Or install manually:
+
 Go to `Cursor Settings` -> `MCP` -> `Add new MCP Server`. Name to your liking, use `command` type with the command `npx @playwright/mcp`. You can also verify config or add command like arguments via clicking `Edit`.
 
 ```js
@@ -106,6 +112,37 @@ Follow the MCP install [guide](https://modelcontextprotocol.io/quickstart/user),
 ```
 </details>
 
+<details>
+<summary><b>Install in Claude Code</b></summary>
+
+Use the Claude Code CLI to add the Playwright MCP server:
+
+```bash
+claude mcp add playwright npx @playwright/mcp@latest
+```
+</details>
+
+<details>
+<summary><b>Install in Qodo Gen</b></summary>
+
+Open [Qodo Gen](https://docs.qodo.ai/qodo-documentation/qodo-gen) chat panel in VSCode or IntelliJ → Connect more tools → + Add new MCP → Paste the following configuration:
+
+```js
+{
+  "mcpServers": {
+    "playwright": {
+      "command": "npx",
+      "args": [
+        "@playwright/mcp@latest"
+      ]
+    }
+  }
+}
+```
+
+Click <code>Save</code>.
+</details>
+
 ### Configuration
 
 Playwright MCP server supports following arguments. They can be provided in the JSON configuration above, as a part of the `"args"` list:
@@ -124,6 +161,7 @@ Playwright MCP server supports following arguments. They can be provided in the
   --block-service-workers      block service workers
   --browser <browser>          browser or chrome channel to use, possible
                                values: chrome, firefox, webkit, msedge.
+  --browser-agent <endpoint>   Use browser agent (experimental).
   --caps <caps>                comma-separated list of capabilities to enable,
                                possible values: tabs, pdf, history, wait, files,
                                install. Default is all.
@@ -137,7 +175,10 @@ Playwright MCP server supports following arguments. They can be provided in the
   --ignore-https-errors        ignore https errors
   --isolated                   keep the browser profile in memory, do not save
                                it to disk.
-  --no-image-responses         do not send image responses to the client.
+  --image-responses <mode>     whether to send image responses to the client.
+                               Can be "allow", "omit", or "auto". Defaults to
+                               "auto", which sends images if the client can
+                               display them.
   --no-sandbox                 disable the sandbox for all process types that
                                are normally sandboxed.
   --output-dir <path>          path to the directory for output files.
@@ -146,6 +187,8 @@ Playwright MCP server supports following arguments. They can be provided in the
                                example ".com,chromium.org,.domain.com"
   --proxy-server <proxy>       specify proxy server, for example
                                "http://myproxy:3128" or "socks5://myproxy:8080"
+  --save-trace                 Whether to save the Playwright Trace of the
+                               session into the output directory.
   --storage-state <path>       path to the storage state file for isolated
                                sessions.
   --user-agent <ua string>     specify user agent string
@@ -194,7 +237,7 @@ state [here](https://playwright.dev/docs/auth).
       "args": [
         "@playwright/mcp@latest",
         "--isolated",
-        "--storage-state={path/to/storage.json}
+        "--storage-state={path/to/storage.json}"
       ]
     }
   }
@@ -349,7 +392,7 @@ http.createServer(async (req, res) => {
   // Creates a headless Playwright MCP server with SSE transport
   const connection = await createConnection({ browser: { launchOptions: { headless: true } } });
   const transport = new SSEServerTransport('/messages', res);
-  await connection.connect(transport);
+  await connection.sever.connect(transport);
 
   // ...
 });

config.d.ts

@@ -23,6 +23,11 @@ export type Config = {
    * The browser to use.
    */
   browser?: {
+    /**
+     * Use browser agent (experimental).
+     */
+    browserAgent?: string;
+
     /**
      * The type of browser to use.
      */
@@ -94,6 +99,11 @@ export type Config = {
    */
   vision?: boolean;
 
+  /**
+   * Whether to save the Playwright trace of the session into the output directory.
+   */
+  saveTrace?: boolean;
+
   /**
    * The directory to save output files.
    */
@@ -112,7 +122,7 @@ export type Config = {
   };
 
   /**
-   * Do not send image responses to the client.
+   * Whether to send image responses to the client. Can be "allow", "omit", or "auto". Defaults to "auto", which sends images if the client can display them.
    */
-  noImageResponses?: boolean;
+  imageResponses?: 'allow' | 'omit' | 'auto';
 };

examples/generate-test.md

@@ -1,4 +1,4 @@
-Generate test for scenario:
+Use Playwright tools to generate test for scenario:
 
 ## GitHub PR Checks Navigation Checklist
 

extension/background.js

@@ -0,0 +1,344 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Simple Chrome Extension that pumps CDP messages between chrome.debugger and WebSocket
+ */
+
+// @ts-check
+
+function debugLog(...args) {
+  const enabled = false;
+  if (enabled) {
+    console.log('[Extension]', ...args);
+  }
+}
+
+class TabShareExtension {
+  constructor() {
+    this.activeConnections = new Map(); // tabId -> connection info
+
+    // Remove page action click handler since we now use popup
+    chrome.tabs.onRemoved.addListener(this.onTabRemoved.bind(this));
+
+    // Handle messages from popup
+    chrome.runtime.onMessage.addListener(this.onMessage.bind(this));
+  }
+
+  /**
+   * Handle messages from popup
+   * @param {any} message
+   * @param {chrome.runtime.MessageSender} sender
+   * @param {Function} sendResponse
+   */
+  onMessage(message, sender, sendResponse) {
+    switch (message.type) {
+      case 'getStatus':
+        this.getStatus(message.tabId, sendResponse);
+        return true; // Will respond asynchronously
+
+      case 'connect':
+        this.connectTab(message.tabId, message.bridgeUrl).then(
+          () => sendResponse({ success: true }),
+          (error) => sendResponse({ success: false, error: error.message })
+        );
+        return true; // Will respond asynchronously
+
+      case 'disconnect':
+        this.disconnectTab(message.tabId).then(
+          () => sendResponse({ success: true }),
+          (error) => sendResponse({ success: false, error: error.message })
+        );
+        return true; // Will respond asynchronously
+    }
+    return false;
+  }
+
+  /**
+   * Get connection status for popup
+   * @param {number} requestedTabId
+   * @param {Function} sendResponse
+   */
+  getStatus(requestedTabId, sendResponse) {
+    const isConnected = this.activeConnections.size > 0;
+    let activeTabId = null;
+    let activeTabInfo = null;
+
+    if (isConnected) {
+      const [tabId, connection] = this.activeConnections.entries().next().value;
+      activeTabId = tabId;
+
+      // Get tab info
+      chrome.tabs.get(tabId, (tab) => {
+        if (chrome.runtime.lastError) {
+          sendResponse({
+            isConnected: false,
+            error: 'Active tab not found'
+          });
+        } else {
+          sendResponse({
+            isConnected: true,
+            activeTabId,
+            activeTabInfo: {
+              title: tab.title,
+              url: tab.url
+            }
+          });
+        }
+      });
+    } else {
+      sendResponse({
+        isConnected: false,
+        activeTabId: null,
+        activeTabInfo: null
+      });
+    }
+  }
+
+  /**
+   * Connect a tab to the bridge server
+   * @param {number} tabId
+   * @param {string} bridgeUrl
+   */
+  async connectTab(tabId, bridgeUrl) {
+    try {
+      debugLog(`Connecting tab ${tabId} to bridge at ${bridgeUrl}`);
+
+      // Attach chrome debugger
+      const debuggee = { tabId };
+      await chrome.debugger.attach(debuggee, '1.3');
+
+      if (chrome.runtime.lastError)
+        throw new Error(chrome.runtime.lastError.message);
+      const targetInfo = /** @type {any} */ (await chrome.debugger.sendCommand(debuggee, 'Target.getTargetInfo'));
+      debugLog('Target info:', targetInfo);
+
+      // Connect to bridge server
+      const socket = new WebSocket(bridgeUrl);
+
+      const connection = {
+        debuggee,
+        socket,
+        tabId,
+        sessionId: `pw-tab-${tabId}`
+      };
+
+      await new Promise((resolve, reject) => {
+        socket.onopen = () => {
+          debugLog(`WebSocket connected for tab ${tabId}`);
+          // Send initial connection info to bridge
+          socket.send(JSON.stringify({
+            type: 'connection_info',
+            sessionId: connection.sessionId,
+            targetInfo: targetInfo?.targetInfo
+          }));
+          resolve(undefined);
+        };
+        socket.onerror = reject;
+        setTimeout(() => reject(new Error('Connection timeout')), 5000);
+      });
+
+      // Set up message handling
+      this.setupMessageHandling(connection);
+
+      // Store connection
+      this.activeConnections.set(tabId, connection);
+
+      // Update UI
+      chrome.action.setBadgeText({ tabId, text: '●' });
+      chrome.action.setBadgeBackgroundColor({ tabId, color: '#4CAF50' });
+      chrome.action.setTitle({ tabId, title: 'Disconnect from Playwright MCP' });
+
+      debugLog(`Tab ${tabId} connected successfully`);
+
+    } catch (error) {
+      debugLog(`Failed to connect tab ${tabId}:`, error.message);
+      await this.cleanupConnection(tabId);
+
+      // Show error to user
+      chrome.action.setBadgeText({ tabId, text: '!' });
+      chrome.action.setBadgeBackgroundColor({ tabId, color: '#F44336' });
+      chrome.action.setTitle({ tabId, title: `Connection failed: ${error.message}` });
+
+      throw error; // Re-throw for popup to handle
+    }
+  }
+
+  /**
+   * Set up bidirectional message handling between debugger and WebSocket
+   * @param {Object} connection
+   */
+  setupMessageHandling(connection) {
+    const { debuggee, socket, tabId, sessionId: rootSessionId } = connection;
+
+    // WebSocket -> chrome.debugger
+    socket.onmessage = async (event) => {
+      let message;
+      try {
+        message = JSON.parse(event.data);
+      } catch (error) {
+        debugLog('Error parsing message:', error);
+        socket.send(JSON.stringify({
+          error: {
+            code: -32700,
+            message: `Error parsing message: ${error.message}`
+          }
+        }));
+        return;
+      }
+
+      try {
+        debugLog('Received from bridge:', message);
+
+        const debuggerSession = { ...debuggee };
+        const sessionId = message.sessionId;
+        // Pass session id, unless it's the root session.
+        if (sessionId && sessionId !== rootSessionId)
+          debuggerSession.sessionId = sessionId;
+
+        // Forward CDP command to chrome.debugger
+        const result = await chrome.debugger.sendCommand(
+          debuggerSession,
+          message.method,
+          message.params || {}
+        );
+
+        // Send response back to bridge
+        const response = {
+          id: message.id,
+          sessionId,
+          result
+        };
+
+        if (chrome.runtime.lastError) {
+          response.error = {
+            code: -32000,
+            message: chrome.runtime.lastError.message,
+          };
+        }
+
+        socket.send(JSON.stringify(response));
+      } catch (error) {
+        debugLog('Error processing WebSocket message:', error);
+        const response = {
+          id: message.id,
+          sessionId: message.sessionId,
+          error: {
+            code: -32000,
+            message: error.message,
+          },
+        };
+        socket.send(JSON.stringify(response));
+      }
+    };
+
+    // chrome.debugger events -> WebSocket
+    const eventListener = (source, method, params) => {
+      if (source.tabId === tabId && socket.readyState === WebSocket.OPEN) {
+        // If the sessionId is not provided, use the root sessionId.
+        const event = {
+          sessionId: source.sessionId || rootSessionId,
+          method,
+          params,
+        };
+        debugLog('Forwarding CDP event:', event);
+        socket.send(JSON.stringify(event));
+      }
+    };
+
+    const detachListener = (source, reason) => {
+      if (source.tabId === tabId) {
+        debugLog(`Debugger detached from tab ${tabId}, reason: ${reason}`);
+        this.disconnectTab(tabId);
+      }
+    };
+
+    // Store listeners for cleanup
+    connection.eventListener = eventListener;
+    connection.detachListener = detachListener;
+
+    chrome.debugger.onEvent.addListener(eventListener);
+    chrome.debugger.onDetach.addListener(detachListener);
+
+    // Handle WebSocket close
+    socket.onclose = () => {
+      debugLog(`WebSocket closed for tab ${tabId}`);
+      this.disconnectTab(tabId);
+    };
+
+    socket.onerror = (error) => {
+      debugLog(`WebSocket error for tab ${tabId}:`, error);
+      this.disconnectTab(tabId);
+    };
+  }
+
+  /**
+   * Disconnect a tab from the bridge
+   * @param {number} tabId
+   */
+  async disconnectTab(tabId) {
+    await this.cleanupConnection(tabId);
+
+    // Update UI
+    chrome.action.setBadgeText({ tabId, text: '' });
+    chrome.action.setTitle({ tabId, title: 'Share tab with Playwright MCP' });
+
+    debugLog(`Tab ${tabId} disconnected`);
+  }
+
+  /**
+   * Clean up connection resources
+   * @param {number} tabId
+   */
+  async cleanupConnection(tabId) {
+    const connection = this.activeConnections.get(tabId);
+    if (!connection) return;
+
+    // Remove listeners
+    if (connection.eventListener) {
+      chrome.debugger.onEvent.removeListener(connection.eventListener);
+    }
+    if (connection.detachListener) {
+      chrome.debugger.onDetach.removeListener(connection.detachListener);
+    }
+
+    // Close WebSocket
+    if (connection.socket && connection.socket.readyState === WebSocket.OPEN) {
+      connection.socket.close();
+    }
+
+    // Detach debugger
+    try {
+      await chrome.debugger.detach(connection.debuggee);
+    } catch (error) {
+      // Ignore detach errors - might already be detached
+    }
+
+    this.activeConnections.delete(tabId);
+  }
+
+  /**
+   * Handle tab removal
+   * @param {number} tabId
+   */
+  async onTabRemoved(tabId) {
+    if (this.activeConnections.has(tabId)) {
+      await this.cleanupConnection(tabId);
+    }
+  }
+}
+
+new TabShareExtension();

extension/manifest.json

@@ -0,0 +1,40 @@
+{
+  "manifest_version": 3,
+  "name": "Playwright MCP Bridge",
+  "version": "1.0.0",
+  "description": "Share browser tabs with Playwright MCP server through CDP bridge",
+
+  "permissions": [
+    "debugger",
+    "activeTab",
+    "tabs",
+    "storage"
+  ],
+
+  "host_permissions": [
+    "<all_urls>"
+  ],
+
+  "background": {
+    "service_worker": "background.js",
+    "type": "module"
+  },
+
+  "action": {
+    "default_title": "Share tab with Playwright MCP",
+    "default_popup": "popup.html",
+    "default_icon": {
+      "16": "icons/icon-16.png",
+      "32": "icons/icon-32.png",
+      "48": "icons/icon-48.png",
+      "128": "icons/icon-128.png"
+    }
+  },
+
+  "icons": {
+    "16": "icons/icon-16.png",
+    "32": "icons/icon-32.png",
+    "48": "icons/icon-48.png",
+    "128": "icons/icon-128.png"
+  }
+}

extension/popup.html

@@ -0,0 +1,173 @@
+<!--
+  Copyright (c) Microsoft Corporation.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <style>
+    body {
+      width: 320px;
+      padding: 16px;
+      font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+      font-size: 14px;
+      margin: 0;
+    }
+
+    .header {
+      margin-bottom: 16px;
+      text-align: center;
+    }
+
+    .header h3 {
+      margin: 0 0 8px 0;
+      color: #333;
+    }
+
+    .section {
+      margin-bottom: 16px;
+    }
+
+    label {
+      display: block;
+      margin-bottom: 4px;
+      font-weight: 500;
+      color: #555;
+    }
+
+    input[type="url"] {
+      width: 100%;
+      padding: 8px;
+      border: 1px solid #ddd;
+      border-radius: 4px;
+      font-size: 14px;
+      box-sizing: border-box;
+    }
+
+    input[type="url"]:focus {
+      outline: none;
+      border-color: #4CAF50;
+      box-shadow: 0 0 0 2px rgba(76, 175, 80, 0.2);
+    }
+
+    .button {
+      background: #4CAF50;
+      color: white;
+      border: none;
+      padding: 10px 16px;
+      border-radius: 4px;
+      cursor: pointer;
+      font-size: 14px;
+      width: 100%;
+      margin-top: 8px;
+    }
+
+    .button:hover {
+      background: #45a049;
+    }
+
+    .button:disabled {
+      background: #cccccc;
+      cursor: not-allowed;
+    }
+
+    .button.disconnect {
+      background: #f44336;
+    }
+
+    .button.disconnect:hover {
+      background: #da190b;
+    }
+
+    .status {
+      padding: 12px;
+      border-radius: 4px;
+      margin-bottom: 16px;
+      text-align: center;
+    }
+
+    .status.connected {
+      background: #e8f5e8;
+      color: #2e7d32;
+      border: 1px solid #4caf50;
+    }
+
+    .status.error {
+      background: #ffebee;
+      color: #c62828;
+      border: 1px solid #f44336;
+    }
+
+    .status.warning {
+      background: #fff3e0;
+      color: #ef6c00;
+      border: 1px solid #ff9800;
+    }
+
+    .tab-info {
+      background: #f5f5f5;
+      padding: 12px;
+      border-radius: 4px;
+      margin-bottom: 16px;
+    }
+
+    .tab-title {
+      font-weight: 500;
+      margin-bottom: 4px;
+      color: #333;
+    }
+
+    .tab-url {
+      font-size: 12px;
+      color: #666;
+      word-break: break-all;
+    }
+
+    .focus-button {
+      background: #2196F3;
+      margin-top: 8px;
+    }
+
+    .focus-button:hover {
+      background: #1976D2;
+    }
+
+    .small-text {
+      font-size: 12px;
+      color: #666;
+      margin-top: 8px;
+    }
+  </style>
+</head>
+<body>
+  <div class="header">
+    <h3>Playwright MCP Bridge</h3>
+  </div>
+
+  <div id="status-container"></div>
+
+  <div class="section">
+    <label for="bridge-url">Bridge Server URL:</label>
+    <input type="url" id="bridge-url" disabled placeholder="ws://localhost:9223/extension" />
+    <div class="small-text">Enter the WebSocket URL of your MCP bridge server</div>
+  </div>
+
+  <div id="action-container">
+    <button id="connect-btn" class="button">Share This Tab</button>
+  </div>
+
+  <script src="popup.js"></script>
+</body>
+</html>

extension/popup.js

@@ -0,0 +1,228 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// @ts-check
+
+/**
+ * Popup script for Playwright MCP Bridge extension
+ */
+
+class PopupController {
+  constructor() {
+    this.currentTab = null;
+    this.bridgeUrlInput = /** @type {HTMLInputElement} */ (document.getElementById('bridge-url'));
+    this.connectBtn = /** @type {HTMLButtonElement} */ (document.getElementById('connect-btn'));
+    this.statusContainer = /** @type {HTMLElement} */ (document.getElementById('status-container'));
+    this.actionContainer = /** @type {HTMLElement} */ (document.getElementById('action-container'));
+
+    this.init();
+  }
+
+  async init() {
+    // Get current tab
+    const [tab] = await chrome.tabs.query({ active: true, currentWindow: true });
+    this.currentTab = tab;
+
+    // Load saved bridge URL
+    const result = await chrome.storage.sync.get(['bridgeUrl']);
+    const savedUrl = result.bridgeUrl || 'ws://localhost:9223/extension';
+    this.bridgeUrlInput.value = savedUrl;
+    this.bridgeUrlInput.disabled = false;
+
+    // Set up event listeners
+    this.bridgeUrlInput.addEventListener('input', this.onUrlChange.bind(this));
+    this.connectBtn.addEventListener('click', this.onConnectClick.bind(this));
+
+    // Update UI based on current state
+    await this.updateUI();
+  }
+
+  async updateUI() {
+    if (!this.currentTab?.id) return;
+
+    // Get connection status from background script
+    const response = await chrome.runtime.sendMessage({
+      type: 'getStatus',
+      tabId: this.currentTab.id
+    });
+
+    const { isConnected, activeTabId, activeTabInfo, error } = response;
+
+    if (!this.statusContainer || !this.actionContainer) return;
+
+    this.statusContainer.innerHTML = '';
+    this.actionContainer.innerHTML = '';
+
+    if (error) {
+      this.showStatus('error', `Error: ${error}`);
+      this.showConnectButton();
+    } else if (isConnected && activeTabId === this.currentTab.id) {
+      // Current tab is connected
+      this.showStatus('connected', 'This tab is currently shared with MCP server');
+      this.showDisconnectButton();
+    } else if (isConnected && activeTabId !== this.currentTab.id) {
+      // Another tab is connected
+      this.showStatus('warning', 'Another tab is already sharing the CDP session');
+      this.showActiveTabInfo(activeTabInfo);
+      this.showFocusButton(activeTabId);
+    } else {
+      // No connection
+      this.showConnectButton();
+    }
+  }
+
+  showStatus(type, message) {
+    const statusDiv = document.createElement('div');
+    statusDiv.className = `status ${type}`;
+    statusDiv.textContent = message;
+    this.statusContainer.appendChild(statusDiv);
+  }
+
+  showConnectButton() {
+    if (!this.actionContainer) return;
+
+    this.actionContainer.innerHTML = `
+      <button id="connect-btn" class="button">Share This Tab</button>
+    `;
+
+    const connectBtn = /** @type {HTMLButtonElement} */ (document.getElementById('connect-btn'));
+    if (connectBtn) {
+      connectBtn.addEventListener('click', this.onConnectClick.bind(this));
+
+      // Disable if URL is invalid
+      const isValidUrl = this.bridgeUrlInput ? this.isValidWebSocketUrl(this.bridgeUrlInput.value) : false;
+      connectBtn.disabled = !isValidUrl;
+    }
+  }
+
+  showDisconnectButton() {
+    if (!this.actionContainer) return;
+
+    this.actionContainer.innerHTML = `
+      <button id="disconnect-btn" class="button disconnect">Stop Sharing</button>
+    `;
+
+    const disconnectBtn = /** @type {HTMLButtonElement} */ (document.getElementById('disconnect-btn'));
+    if (disconnectBtn) {
+      disconnectBtn.addEventListener('click', this.onDisconnectClick.bind(this));
+    }
+  }
+
+  showActiveTabInfo(tabInfo) {
+    if (!tabInfo) return;
+
+    const tabDiv = document.createElement('div');
+    tabDiv.className = 'tab-info';
+    tabDiv.innerHTML = `
+      <div class="tab-title">${tabInfo.title || 'Unknown Tab'}</div>
+      <div class="tab-url">${tabInfo.url || ''}</div>
+    `;
+    this.statusContainer.appendChild(tabDiv);
+  }
+
+  showFocusButton(activeTabId) {
+    if (!this.actionContainer) return;
+
+    this.actionContainer.innerHTML = `
+      <button id="focus-btn" class="button focus-button">Switch to Shared Tab</button>
+    `;
+
+    const focusBtn = /** @type {HTMLButtonElement} */ (document.getElementById('focus-btn'));
+    if (focusBtn) {
+      focusBtn.addEventListener('click', () => this.onFocusClick(activeTabId));
+    }
+  }
+
+  onUrlChange() {
+    if (!this.bridgeUrlInput) return;
+
+    const isValid = this.isValidWebSocketUrl(this.bridgeUrlInput.value);
+    const connectBtn = /** @type {HTMLButtonElement} */ (document.getElementById('connect-btn'));
+    if (connectBtn) {
+      connectBtn.disabled = !isValid;
+    }
+
+    // Save URL to storage
+    if (isValid) {
+      chrome.storage.sync.set({ bridgeUrl: this.bridgeUrlInput.value });
+    }
+  }
+
+  async onConnectClick() {
+    if (!this.bridgeUrlInput || !this.currentTab?.id) return;
+
+    const url = this.bridgeUrlInput.value.trim();
+    if (!this.isValidWebSocketUrl(url)) {
+      this.showStatus('error', 'Please enter a valid WebSocket URL');
+      return;
+    }
+
+    // Save URL to storage
+    await chrome.storage.sync.set({ bridgeUrl: url });
+
+    // Send connect message to background script
+    const response = await chrome.runtime.sendMessage({
+      type: 'connect',
+      tabId: this.currentTab.id,
+      bridgeUrl: url
+    });
+
+    if (response.success) {
+      await this.updateUI();
+    } else {
+      this.showStatus('error', response.error || 'Failed to connect');
+    }
+  }
+
+  async onDisconnectClick() {
+    if (!this.currentTab?.id) return;
+
+    const response = await chrome.runtime.sendMessage({
+      type: 'disconnect',
+      tabId: this.currentTab.id
+    });
+
+    if (response.success) {
+      await this.updateUI();
+    } else {
+      this.showStatus('error', response.error || 'Failed to disconnect');
+    }
+  }
+
+  async onFocusClick(activeTabId) {
+    try {
+      await chrome.tabs.update(activeTabId, { active: true });
+      window.close(); // Close popup after switching
+    } catch (error) {
+      this.showStatus('error', 'Failed to switch to tab');
+    }
+  }
+
+  isValidWebSocketUrl(url) {
+    if (!url) return false;
+    try {
+      const parsed = new URL(url);
+      return parsed.protocol === 'ws:' || parsed.protocol === 'wss:';
+    } catch {
+      return false;
+    }
+  }
+}
+
+// Initialize popup when DOM is loaded
+document.addEventListener('DOMContentLoaded', () => {
+  new PopupController();
+});

index.d.ts

@@ -16,14 +16,13 @@
  */
 
 import type { Server } from '@modelcontextprotocol/sdk/server/index.js';
-import type { Config } from './config';
-import type { Transport } from '@modelcontextprotocol/sdk/shared/transport.js';
+import type { Config } from './config.js';
+import type { BrowserContext } from 'playwright';
 
 export type Connection = {
   server: Server;
-  connect(transport: Transport): Promise<void>;
   close(): Promise<void>;
 };
 
-export declare function createConnection(config?: Config): Promise<Connection>;
+export declare function createConnection(config?: Config, contextGetter?: () => Promise<BrowserContext>): Promise<Connection>;
 export {};

index.js

@@ -15,5 +15,5 @@
  * limitations under the License.
  */
 
-import { createConnection } from './lib/index';
+import { createConnection } from './lib/index.js';
 export { createConnection };

package-lock.json

@@ -1,17 +1,20 @@
 {
   "name": "@playwright/mcp",
-  "version": "0.0.25",
+  "version": "0.0.29",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@playwright/mcp",
-      "version": "0.0.25",
+      "version": "0.0.29",
       "license": "Apache-2.0",
       "dependencies": {
         "@modelcontextprotocol/sdk": "^1.11.0",
         "commander": "^13.1.0",
-        "playwright": "1.53.0-alpha-1746832516000",
+        "debug": "^4.4.1",
+        "mime": "^4.0.7",
+        "playwright": "1.53.0",
+        "ws": "^8.18.1",
         "zod-to-json-schema": "^3.24.4"
       },
       "bin": {
@@ -20,9 +23,12 @@
       "devDependencies": {
         "@eslint/eslintrc": "^3.2.0",
         "@eslint/js": "^9.19.0",
-        "@playwright/test": "1.53.0-alpha-1746832516000",
+        "@playwright/test": "1.53.0",
         "@stylistic/eslint-plugin": "^3.0.1",
+        "@types/chrome": "^0.0.315",
+        "@types/debug": "^4.1.12",
         "@types/node": "^22.13.10",
+        "@types/ws": "^8.18.1",
         "@typescript-eslint/eslint-plugin": "^8.26.1",
         "@typescript-eslint/parser": "^8.26.1",
         "@typescript-eslint/utils": "^8.26.1",
@@ -286,13 +292,12 @@
       }
     },
     "node_modules/@playwright/test": {
-      "version": "1.53.0-alpha-1746832516000",
-      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.53.0-alpha-1746832516000.tgz",
-      "integrity": "sha512-Sec+6uzpA4MfwmQqJFBFVazffynqVwLO5swDxG7WoqgpUdn9gQX4K4tDG64SV6f4nOpwdM5LKTasPSXu02nn/Q==",
+      "version": "1.53.0",
+      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.53.0.tgz",
+      "integrity": "sha512-15hjKreZDcp7t6TL/7jkAo6Df5STZN09jGiv5dbP9A6vMVncXRqE7/B2SncsyOwrkZRBH2i6/TPOL8BVmm3c7w==",
       "dev": true,
-      "license": "Apache-2.0",
       "dependencies": {
-        "playwright": "1.53.0-alpha-1746832516000"
+        "playwright": "1.53.0"
       },
       "bin": {
         "playwright": "cli.js"
@@ -354,6 +359,27 @@
         "url": "https://github.com/sponsors/jonschlinkert"
       }
     },
+    "node_modules/@types/chrome": {
+      "version": "0.0.315",
+      "resolved": "https://registry.npmjs.org/@types/chrome/-/chrome-0.0.315.tgz",
+      "integrity": "sha512-Oy1dYWkr6BCmgwBtOngLByCHstQ3whltZg7/7lubgIZEYvKobDneqplgc6LKERNRBwckFviV4UU5AZZNUFrJ4A==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/filesystem": "*",
+        "@types/har-format": "*"
+      }
+    },
+    "node_modules/@types/debug": {
+      "version": "4.1.12",
+      "resolved": "https://registry.npmjs.org/@types/debug/-/debug-4.1.12.tgz",
+      "integrity": "sha512-vIChWdVG3LG1SMxEvI/AK+FWJthlrqlTu7fbrlywTkkaONwk/UAGaULXRlf8vkzFBLVm0zkMdCquhL5aOjhXPQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/ms": "*"
+      }
+    },
     "node_modules/@types/estree": {
       "version": "1.0.6",
       "resolved": "https://registry.npmjs.org/@types/estree/-/estree-1.0.6.tgz",
@@ -361,6 +387,30 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/filesystem": {
+      "version": "0.0.36",
+      "resolved": "https://registry.npmjs.org/@types/filesystem/-/filesystem-0.0.36.tgz",
+      "integrity": "sha512-vPDXOZuannb9FZdxgHnqSwAG/jvdGM8Wq+6N4D/d80z+D4HWH+bItqsZaVRQykAn6WEVeEkLm2oQigyHtgb0RA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/filewriter": "*"
+      }
+    },
+    "node_modules/@types/filewriter": {
+      "version": "0.0.33",
+      "resolved": "https://registry.npmjs.org/@types/filewriter/-/filewriter-0.0.33.tgz",
+      "integrity": "sha512-xFU8ZXTw4gd358lb2jw25nxY9QAgqn2+bKKjKOYfNCzN4DKCFetK7sPtrlpg66Ywe3vWY9FNxprZawAh9wfJ3g==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@types/har-format": {
+      "version": "1.2.16",
+      "resolved": "https://registry.npmjs.org/@types/har-format/-/har-format-1.2.16.tgz",
+      "integrity": "sha512-fluxdy7ryD3MV6h8pTfTYpy/xQzCFC7m89nOH9y94cNqJ1mDIDPut7MnRHI3F6qRmh/cT2fUjG1MLdCNb4hE9A==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@types/json-schema": {
       "version": "7.0.15",
       "resolved": "https://registry.npmjs.org/@types/json-schema/-/json-schema-7.0.15.tgz",
@@ -375,6 +425,13 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@types/ms": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/@types/ms/-/ms-2.1.0.tgz",
+      "integrity": "sha512-GsCCIZDE/p3i96vtEqx+7dBUGXrc7zeSK3wwPHIaRThS+9OhWIXRqzs4d6k1SVU8g91DrNRWxWUGhp5KXQb2VA==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@types/node": {
       "version": "22.13.10",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-22.13.10.tgz",
@@ -385,6 +442,16 @@
         "undici-types": "~6.20.0"
       }
     },
+    "node_modules/@types/ws": {
+      "version": "8.18.1",
+      "resolved": "https://registry.npmjs.org/@types/ws/-/ws-8.18.1.tgz",
+      "integrity": "sha512-ThVF6DCVhA8kUGy+aazFQ4kXQ7E1Ty7A3ypFOe0IcJV8O/M511G99AW24irKrW56Wt44yG9+ij8FaqoBGkuBXg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@typescript-eslint/eslint-plugin": {
       "version": "8.27.0",
       "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.27.0.tgz",
@@ -834,16 +901,16 @@
       "license": "MIT"
     },
     "node_modules/body-parser": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-2.1.0.tgz",
-      "integrity": "sha512-/hPxh61E+ll0Ujp24Ilm64cykicul1ypfwjVttduAiEdtnJFvLePSrIPk+HMImtNv5270wOGCb1Tns2rybMkoQ==",
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-2.2.0.tgz",
+      "integrity": "sha512-02qvAaxv8tp7fBa/mw1ga98OGm+eCbqzJOKoRt70sLmfEEi+jyBYVTDGfCL/k06/4EMk/z01gCe7HoCH/f2LTg==",
       "license": "MIT",
       "dependencies": {
         "bytes": "^3.1.2",
         "content-type": "^1.0.5",
         "debug": "^4.4.0",
         "http-errors": "^2.0.0",
-        "iconv-lite": "^0.5.2",
+        "iconv-lite": "^0.6.3",
         "on-finished": "^2.4.1",
         "qs": "^6.14.0",
         "raw-body": "^3.0.0",
@@ -853,44 +920,6 @@
         "node": ">=18"
       }
     },
-    "node_modules/body-parser/node_modules/debug": {
-      "version": "4.4.0",
-      "resolved": "https://registry.npmjs.org/debug/-/debug-4.4.0.tgz",
-      "integrity": "sha512-6WTZ/IxCY/T6BALoZHaE4ctp9xm+Z5kY/pzYaCHRFeyVhojxlrm+46y68HA6hr0TcwEssoxNiDEUJQjfPZ/RYA==",
-      "license": "MIT",
-      "dependencies": {
-        "ms": "^2.1.3"
-      },
-      "engines": {
-        "node": ">=6.0"
-      },
-      "peerDependenciesMeta": {
-        "supports-color": {
-          "optional": true
-        }
-      }
-    },
-    "node_modules/body-parser/node_modules/ms": {
-      "version": "2.1.3",
-      "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.3.tgz",
-      "integrity": "sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA==",
-      "license": "MIT"
-    },
-    "node_modules/body-parser/node_modules/qs": {
-      "version": "6.14.0",
-      "resolved": "https://registry.npmjs.org/qs/-/qs-6.14.0.tgz",
-      "integrity": "sha512-YWWTjgABSKcvs/nWBi9PycY/JiPJqOD4JA6o9Sej2AtvSGarXxKC3OQSk4pAarbdQlKAh5D4FCQkJNkW+GAn3w==",
-      "license": "BSD-3-Clause",
-      "dependencies": {
-        "side-channel": "^1.1.0"
-      },
-      "engines": {
-        "node": ">=0.6"
-      },
-      "funding": {
-        "url": "https://github.com/sponsors/ljharb"
-      }
-    },
     "node_modules/brace-expansion": {
       "version": "1.1.11",
       "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
@@ -1156,12 +1185,12 @@
       }
     },
     "node_modules/debug": {
-      "version": "4.3.6",
-      "resolved": "https://registry.npmjs.org/debug/-/debug-4.3.6.tgz",
-      "integrity": "sha512-O/09Bd4Z1fBrU4VzkhFqVgpPzaGbw6Sm9FEkBT1A/YBXQFGuuSxa1dN2nxgxS34JmKXqYx8CZAwEVoJFImUXIg==",
+      "version": "4.4.1",
+      "resolved": "https://registry.npmjs.org/debug/-/debug-4.4.1.tgz",
+      "integrity": "sha512-KcKCqiftBJcZr++7ykoDIEwSa3XWowTfNPo92BYxjXiyYEVrUQh2aLyhxBCwww+heortUFxEJYcRzosstTEBYQ==",
       "license": "MIT",
       "dependencies": {
-        "ms": "2.1.2"
+        "ms": "^2.1.3"
       },
       "engines": {
         "node": ">=6.0"
@@ -1224,16 +1253,6 @@
         "node": ">= 0.8"
       }
     },
-    "node_modules/destroy": {
-      "version": "1.2.0",
-      "resolved": "https://registry.npmjs.org/destroy/-/destroy-1.2.0.tgz",
-      "integrity": "sha512-2sJGJTaXIIaR1w4iJSNoN0hnMY7Gpc/n8D4qSCJw8QqFWXf7cuAgnEHxBpweaVcPevC2l3KpjYCx3NypQQgaJg==",
-      "license": "MIT",
-      "engines": {
-        "node": ">= 0.8",
-        "npm": "1.2.8000 || >= 1.4.16"
-      }
-    },
     "node_modules/doctrine": {
       "version": "2.1.0",
       "resolved": "https://registry.npmjs.org/doctrine/-/doctrine-2.1.0.tgz",
@@ -1769,46 +1788,45 @@
       }
     },
     "node_modules/express": {
-      "version": "5.0.1",
-      "resolved": "https://registry.npmjs.org/express/-/express-5.0.1.tgz",
-      "integrity": "sha512-ORF7g6qGnD+YtUG9yx4DFoqCShNMmUKiXuT5oWMHiOvt/4WFbHC6yCwQMTSBMno7AqntNCAzzcnnjowRkTL9eQ==",
+      "version": "5.1.0",
+      "resolved": "https://registry.npmjs.org/express/-/express-5.1.0.tgz",
+      "integrity": "sha512-DT9ck5YIRU+8GYzzU5kT3eHGA5iL+1Zd0EutOmTE9Dtk+Tvuzd23VBU+ec7HPNSTxXYO55gPV/hq4pSBJDjFpA==",
       "license": "MIT",
       "dependencies": {
         "accepts": "^2.0.0",
-        "body-parser": "^2.0.1",
+        "body-parser": "^2.2.0",
         "content-disposition": "^1.0.0",
-        "content-type": "~1.0.4",
-        "cookie": "0.7.1",
+        "content-type": "^1.0.5",
+        "cookie": "^0.7.1",
         "cookie-signature": "^1.2.1",
-        "debug": "4.3.6",
-        "depd": "2.0.0",
-        "encodeurl": "~2.0.0",
-        "escape-html": "~1.0.3",
-        "etag": "~1.8.1",
-        "finalhandler": "^2.0.0",
-        "fresh": "2.0.0",
-        "http-errors": "2.0.0",
+        "debug": "^4.4.0",
+        "encodeurl": "^2.0.0",
+        "escape-html": "^1.0.3",
+        "etag": "^1.8.1",
+        "finalhandler": "^2.1.0",
+        "fresh": "^2.0.0",
+        "http-errors": "^2.0.0",
         "merge-descriptors": "^2.0.0",
-        "methods": "~1.1.2",
         "mime-types": "^3.0.0",
-        "on-finished": "2.4.1",
-        "once": "1.4.0",
-        "parseurl": "~1.3.3",
-        "proxy-addr": "~2.0.7",
-        "qs": "6.13.0",
-        "range-parser": "~1.2.1",
-        "router": "^2.0.0",
-        "safe-buffer": "5.2.1",
+        "on-finished": "^2.4.1",
+        "once": "^1.4.0",
+        "parseurl": "^1.3.3",
+        "proxy-addr": "^2.0.7",
+        "qs": "^6.14.0",
+        "range-parser": "^1.2.1",
+        "router": "^2.2.0",
         "send": "^1.1.0",
-        "serve-static": "^2.1.0",
-        "setprototypeof": "1.2.0",
-        "statuses": "2.0.1",
-        "type-is": "^2.0.0",
-        "utils-merge": "1.0.1",
-        "vary": "~1.1.2"
+        "serve-static": "^2.2.0",
+        "statuses": "^2.0.1",
+        "type-is": "^2.0.1",
+        "vary": "^1.1.2"
       },
       "engines": {
         "node": ">= 18"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/express"
       }
     },
     "node_modules/express-rate-limit": {
@@ -1930,29 +1948,6 @@
         "node": ">= 0.8"
       }
     },
-    "node_modules/finalhandler/node_modules/debug": {
-      "version": "4.4.0",
-      "resolved": "https://registry.npmjs.org/debug/-/debug-4.4.0.tgz",
-      "integrity": "sha512-6WTZ/IxCY/T6BALoZHaE4ctp9xm+Z5kY/pzYaCHRFeyVhojxlrm+46y68HA6hr0TcwEssoxNiDEUJQjfPZ/RYA==",
-      "license": "MIT",
-      "dependencies": {
-        "ms": "^2.1.3"
-      },
-      "engines": {
-        "node": ">=6.0"
-      },
-      "peerDependenciesMeta": {
-        "supports-color": {
-          "optional": true
-        }
-      }
-    },
-    "node_modules/finalhandler/node_modules/ms": {
-      "version": "2.1.3",
-      "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.3.tgz",
-      "integrity": "sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA==",
-      "license": "MIT"
-    },
     "node_modules/find-root": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/find-root/-/find-root-1.1.0.tgz",
@@ -2037,7 +2032,6 @@
       "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-2.3.2.tgz",
       "integrity": "sha512-xiqMQR4xAeHTuB9uWm+fFRcIOgKBMiOBP+eXiyT7jsgVCq1bkVygt00oASowB7EdtpOHaaPgKt812P9ab+DDKA==",
       "hasInstallScript": true,
-      "license": "MIT",
       "optional": true,
       "os": [
         "darwin"
@@ -2312,12 +2306,12 @@
       }
     },
     "node_modules/iconv-lite": {
-      "version": "0.5.2",
-      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.5.2.tgz",
-      "integrity": "sha512-kERHXvpSaB4aU3eANwidg79K8FlrN77m8G9V+0vOR3HYaRifrlwMEpT7ZBJqLSEIHnEgJTHcWK82wwLwwKwtag==",
+      "version": "0.6.3",
+      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.6.3.tgz",
+      "integrity": "sha512-4fCk79wshMdzMp2rH06qWrJE4iolqLhCUH+OiuIgU++RB0+94NlDL81atO7GX55uUKueo0txHNtvEyI6D7WdMw==",
       "license": "MIT",
       "dependencies": {
-        "safer-buffer": ">= 2.1.2 < 3"
+        "safer-buffer": ">= 2.1.2 < 3.0.0"
       },
       "engines": {
         "node": ">=0.10.0"
@@ -2928,15 +2922,6 @@
         "node": ">= 8"
       }
     },
-    "node_modules/methods": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/methods/-/methods-1.1.2.tgz",
-      "integrity": "sha512-iclAHeNqNm68zFtnZ0e+1L2yUIdvzNoauKU4WBA3VvH/vPFieF7qfRlwUZU+DA9P9bPXIS90ulxoUoCH23sV2w==",
-      "license": "MIT",
-      "engines": {
-        "node": ">= 0.6"
-      }
-    },
     "node_modules/metric-lcs": {
       "version": "0.1.2",
       "resolved": "https://registry.npmjs.org/metric-lcs/-/metric-lcs-0.1.2.tgz",
@@ -2958,6 +2943,21 @@
         "node": ">=8.6"
       }
     },
+    "node_modules/mime": {
+      "version": "4.0.7",
+      "resolved": "https://registry.npmjs.org/mime/-/mime-4.0.7.tgz",
+      "integrity": "sha512-2OfDPL+e03E0LrXaGYOtTFIYhiuzep94NSsuhrNULq+stylcJedcHdzHtz0atMUuGwJfFYs0YL5xeC/Ca2x0eQ==",
+      "funding": [
+        "https://github.com/sponsors/broofa"
+      ],
+      "license": "MIT",
+      "bin": {
+        "mime": "bin/cli.js"
+      },
+      "engines": {
+        "node": ">=16"
+      }
+    },
     "node_modules/mime-db": {
       "version": "1.54.0",
       "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.54.0.tgz",
@@ -2968,12 +2968,12 @@
       }
     },
     "node_modules/mime-types": {
-      "version": "3.0.0",
-      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-3.0.0.tgz",
-      "integrity": "sha512-XqoSHeCGjVClAmoGFG3lVFqQFRIrTVw2OH3axRqAcfaw+gHWIfnASS92AV+Rl/mk0MupgZTRHQOjxY6YVnzK5w==",
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-3.0.1.tgz",
+      "integrity": "sha512-xRc4oEhT6eaBpU1XF7AjpOFD+xQmXNB5OVKwp4tqCuBpHLS/ZbBDrc07mYTDqVMg6PfxUjjNp85O6Cd2Z/5HWA==",
       "license": "MIT",
       "dependencies": {
-        "mime-db": "^1.53.0"
+        "mime-db": "^1.54.0"
       },
       "engines": {
         "node": ">= 0.6"
@@ -3003,9 +3003,9 @@
       }
     },
     "node_modules/ms": {
-      "version": "2.1.2",
-      "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.2.tgz",
-      "integrity": "sha512-sGkPx+VjMtmA6MX27oA4FBFELFCZZ4S4XqeGOXCv68tT+jb3vk/RyaKWP0PTKyWtmLSM0b+adUTEvbs1PEaH2w==",
+      "version": "2.1.3",
+      "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.3.tgz",
+      "integrity": "sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA==",
       "license": "MIT"
     },
     "node_modules/natural-compare": {
@@ -3298,12 +3298,11 @@
       }
     },
     "node_modules/playwright": {
-      "version": "1.53.0-alpha-1746832516000",
-      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.53.0-alpha-1746832516000.tgz",
-      "integrity": "sha512-kcC1B2XJr4VaDAcVzi61SbYGkodq1QIqQXuPieXsNgZZ7cEKWzO2sI42yp2yie6wlCx0oLkSS2Q6jWSRVRLeaw==",
-      "license": "Apache-2.0",
+      "version": "1.53.0",
+      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.53.0.tgz",
+      "integrity": "sha512-ghGNnIEYZC4E+YtclRn4/p6oYbdPiASELBIYkBXfaTVKreQUYbMUYQDwS12a8F0/HtIjr/CkGjtwABeFPGcS4Q==",
       "dependencies": {
-        "playwright-core": "1.53.0-alpha-1746832516000"
+        "playwright-core": "1.53.0"
       },
       "bin": {
         "playwright": "cli.js"
@@ -3316,10 +3315,9 @@
       }
     },
     "node_modules/playwright-core": {
-      "version": "1.53.0-alpha-1746832516000",
-      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.53.0-alpha-1746832516000.tgz",
-      "integrity": "sha512-4O98y4zV0rOP6CepMLC/VGuzqGaR1sS9AVh+i0CghWMQHM/8bxPJI8W38QndO0JU0V5nBD6j7DQeNt1mJ+CZ+g==",
-      "license": "Apache-2.0",
+      "version": "1.53.0",
+      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.53.0.tgz",
+      "integrity": "sha512-mGLg8m0pm4+mmtB7M89Xw/GSqoNC+twivl8ITteqvAndachozYe2ZA7srU6uleV1vEdAHYqjq+SV8SNxRRFYBw==",
       "bin": {
         "playwright-core": "cli.js"
       },
@@ -3371,12 +3369,12 @@
       }
     },
     "node_modules/qs": {
-      "version": "6.13.0",
-      "resolved": "https://registry.npmjs.org/qs/-/qs-6.13.0.tgz",
-      "integrity": "sha512-+38qI9SOr8tfZ4QmJNplMUxqjbe7LKvvZgWdExBOmd+egZTtjLB67Gu0HRX3u/XOq7UU2Nx6nsjvS16Z9uwfpg==",
+      "version": "6.14.0",
+      "resolved": "https://registry.npmjs.org/qs/-/qs-6.14.0.tgz",
+      "integrity": "sha512-YWWTjgABSKcvs/nWBi9PycY/JiPJqOD4JA6o9Sej2AtvSGarXxKC3OQSk4pAarbdQlKAh5D4FCQkJNkW+GAn3w==",
       "license": "BSD-3-Clause",
       "dependencies": {
-        "side-channel": "^1.0.6"
+        "side-channel": "^1.1.0"
       },
       "engines": {
         "node": ">=0.6"
@@ -3430,18 +3428,6 @@
         "node": ">= 0.8"
       }
     },
-    "node_modules/raw-body/node_modules/iconv-lite": {
-      "version": "0.6.3",
-      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.6.3.tgz",
-      "integrity": "sha512-4fCk79wshMdzMp2rH06qWrJE4iolqLhCUH+OiuIgU++RB0+94NlDL81atO7GX55uUKueo0txHNtvEyI6D7WdMw==",
-      "license": "MIT",
-      "dependencies": {
-        "safer-buffer": ">= 2.1.2 < 3.0.0"
-      },
-      "engines": {
-        "node": ">=0.10.0"
-      }
-    },
     "node_modules/reflect.getprototypeof": {
       "version": "1.0.10",
       "resolved": "https://registry.npmjs.org/reflect.getprototypeof/-/reflect.getprototypeof-1.0.10.tgz",
@@ -3529,11 +3515,13 @@
       }
     },
     "node_modules/router": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/router/-/router-2.1.0.tgz",
-      "integrity": "sha512-/m/NSLxeYEgWNtyC+WtNHCF7jbGxOibVWKnn+1Psff4dJGOfoXP+MuC/f2CwSmyiHdOIzYnYFp4W6GxWfekaLA==",
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/router/-/router-2.2.0.tgz",
+      "integrity": "sha512-nLTrUKm2UyiL7rlhapu/Zl45FwNgkZGaCpZbIHajDYgwlJCOzLSk+cIPAnsEqV955GjILJnKbdQC1nVPz+gAYQ==",
       "license": "MIT",
       "dependencies": {
+        "debug": "^4.4.0",
+        "depd": "^2.0.0",
         "is-promise": "^4.0.0",
         "parseurl": "^1.3.3",
         "path-to-regexp": "^8.0.0"
@@ -3661,19 +3649,18 @@
       }
     },
     "node_modules/send": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/send/-/send-1.1.0.tgz",
-      "integrity": "sha512-v67WcEouB5GxbTWL/4NeToqcZiAWEq90N888fczVArY8A79J0L4FD7vj5hm3eUMua5EpoQ59wa/oovY6TLvRUA==",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/send/-/send-1.2.0.tgz",
+      "integrity": "sha512-uaW0WwXKpL9blXE2o0bRhoL2EGXIrZxQ2ZQ4mgcfoBxdFmQold+qWsD2jLrfZ0trjKL6vOw0j//eAwcALFjKSw==",
       "license": "MIT",
       "dependencies": {
         "debug": "^4.3.5",
-        "destroy": "^1.2.0",
         "encodeurl": "^2.0.0",
         "escape-html": "^1.0.3",
         "etag": "^1.8.1",
-        "fresh": "^0.5.2",
+        "fresh": "^2.0.0",
         "http-errors": "^2.0.0",
-        "mime-types": "^2.1.35",
+        "mime-types": "^3.0.1",
         "ms": "^2.1.3",
         "on-finished": "^2.4.1",
         "range-parser": "^1.2.1",
@@ -3683,52 +3670,16 @@
         "node": ">= 18"
       }
     },
-    "node_modules/send/node_modules/fresh": {
-      "version": "0.5.2",
-      "resolved": "https://registry.npmjs.org/fresh/-/fresh-0.5.2.tgz",
-      "integrity": "sha512-zJ2mQYM18rEFOudeV4GShTGIQ7RbzA7ozbU9I/XBpm7kqgMywgmylMwXHxZJmkVoYkna9d2pVXVXPdYTP9ej8Q==",
-      "license": "MIT",
-      "engines": {
-        "node": ">= 0.6"
-      }
-    },
-    "node_modules/send/node_modules/mime-db": {
-      "version": "1.52.0",
-      "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.52.0.tgz",
-      "integrity": "sha512-sPU4uV7dYlvtWJxwwxHD0PuihVNiE7TyAbQ5SWxDCB9mUYvOgroQOwYQQOKPJ8CIbE+1ETVlOoK1UC2nU3gYvg==",
-      "license": "MIT",
-      "engines": {
-        "node": ">= 0.6"
-      }
-    },
-    "node_modules/send/node_modules/mime-types": {
-      "version": "2.1.35",
-      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.35.tgz",
-      "integrity": "sha512-ZDY+bPm5zTTF+YpCrAU9nK0UgICYPT0QtT1NZWFv4s++TNkcgVaT0g6+4R2uI4MjQjzysHB1zxuWL50hzaeXiw==",
-      "license": "MIT",
-      "dependencies": {
-        "mime-db": "1.52.0"
-      },
-      "engines": {
-        "node": ">= 0.6"
-      }
-    },
-    "node_modules/send/node_modules/ms": {
-      "version": "2.1.3",
-      "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.3.tgz",
-      "integrity": "sha512-6FlzubTLZG3J2a/NVCAleEhjzq5oxgHyaCU9yYXvcLsvoVaHJq/s5xXI6/XXP6tz7R9xAOtHnSO/tXtF3WRTlA==",
-      "license": "MIT"
-    },
     "node_modules/serve-static": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/serve-static/-/serve-static-2.1.0.tgz",
-      "integrity": "sha512-A3We5UfEjG8Z7VkDv6uItWw6HY2bBSBJT1KtVESn6EOoOr2jAxNhxWCLY3jDE2WcuHXByWju74ck3ZgLwL8xmA==",
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/serve-static/-/serve-static-2.2.0.tgz",
+      "integrity": "sha512-61g9pCh0Vnh7IutZjtLGGpTA355+OPn2TyDv/6ivP2h/AdAVX9azsoxmg2/M6nZeQZNYBEwIcsne1mJd9oQItQ==",
       "license": "MIT",
       "dependencies": {
         "encodeurl": "^2.0.0",
         "escape-html": "^1.0.3",
         "parseurl": "^1.3.3",
-        "send": "^1.0.0"
+        "send": "^1.2.0"
       },
       "engines": {
         "node": ">= 18"
@@ -4061,9 +4012,9 @@
       }
     },
     "node_modules/type-is": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/type-is/-/type-is-2.0.0.tgz",
-      "integrity": "sha512-gd0sGezQYCbWSbkZr75mln4YBidWUN60+devscpLF5mtRDUpiaTvKpBNrdaCvel1NdR2k6vclXybU5fBd2i+nw==",
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/type-is/-/type-is-2.0.1.tgz",
+      "integrity": "sha512-OZs6gsjF4vMp32qrCbiVSkrFmXtG/AZhY3t0iAMrMBiAZyV9oALtXO8hsrHbMXF9x6L3grlFuwW2oAz7cav+Gw==",
       "license": "MIT",
       "dependencies": {
         "content-type": "^1.0.5",
@@ -4211,15 +4162,6 @@
         "punycode": "^2.1.0"
       }
     },
-    "node_modules/utils-merge": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/utils-merge/-/utils-merge-1.0.1.tgz",
-      "integrity": "sha512-pMZTvIkT1d+TFGvDOqodOclx0QWkkgi6Tdoa8gC8ffGAAqz9pzPTZWAybbsHHoED/ztMtkv/VoYTYyShUn81hA==",
-      "license": "MIT",
-      "engines": {
-        "node": ">= 0.4.0"
-      }
-    },
     "node_modules/vary": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
@@ -4349,6 +4291,27 @@
       "integrity": "sha512-l4Sp/DRseor9wL6EvV2+TuQn63dMkPjZ/sp9XkghTEbV9KlPS1xUsZ3u7/IQO4wxtcFB4bgpQPRcR3QCvezPcQ==",
       "license": "ISC"
     },
+    "node_modules/ws": {
+      "version": "8.18.1",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-8.18.1.tgz",
+      "integrity": "sha512-RKW2aJZMXeMxVpnZ6bck+RswznaxmzdULiBr6KY7XkTnW8uvt0iT9H5DkHUChXrc+uurzwa0rVI16n/Xzjdz1w==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=10.0.0"
+      },
+      "peerDependencies": {
+        "bufferutil": "^4.0.1",
+        "utf-8-validate": ">=5.0.2"
+      },
+      "peerDependenciesMeta": {
+        "bufferutil": {
+          "optional": true
+        },
+        "utf-8-validate": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/yocto-queue": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/yocto-queue/-/yocto-queue-0.1.0.tgz",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@playwright/mcp",
-  "version": "0.0.25",
+  "version": "0.0.29",
   "description": "Playwright Tools for MCP",
   "type": "module",
   "repository": {
@@ -24,6 +24,8 @@
     "ctest": "playwright test --project=chrome",
     "ftest": "playwright test --project=firefox",
     "wtest": "playwright test --project=webkit",
+    "etest": "playwright test --project=chromium-extension",
+    "run-server": "node lib/browserServer.js",
     "clean": "rm -rf lib",
     "npm-publish": "npm run clean && npm run build && npm run test && npm publish"
   },
@@ -37,15 +39,21 @@
   "dependencies": {
     "@modelcontextprotocol/sdk": "^1.11.0",
     "commander": "^13.1.0",
-    "playwright": "1.53.0-alpha-1746832516000",
+    "debug": "^4.4.1",
+    "mime": "^4.0.7",
+    "playwright": "1.53.0",
+    "ws": "^8.18.1",
     "zod-to-json-schema": "^3.24.4"
   },
   "devDependencies": {
     "@eslint/eslintrc": "^3.2.0",
     "@eslint/js": "^9.19.0",
-    "@playwright/test": "1.53.0-alpha-1746832516000",
+    "@playwright/test": "1.53.0",
     "@stylistic/eslint-plugin": "^3.0.1",
+    "@types/chrome": "^0.0.315",
+    "@types/debug": "^4.1.12",
     "@types/node": "^22.13.10",
+    "@types/ws": "^8.18.1",
     "@typescript-eslint/eslint-plugin": "^8.26.1",
     "@typescript-eslint/parser": "^8.26.1",
     "@typescript-eslint/utils": "^8.26.1",

playwright.config.ts

@@ -29,8 +29,16 @@ export default defineConfig<TestOptions>({
     { name: 'chrome' },
     { name: 'msedge', use: { mcpBrowser: 'msedge' } },
     { name: 'chromium', use: { mcpBrowser: 'chromium' } },
-    ...process.env.MCP_IN_DOCKER ? [{ name: 'chromium-docker', use: { mcpBrowser: 'chromium', mcpMode: 'docker' as const } }] : [],
+    ...process.env.MCP_IN_DOCKER ? [{
+      name: 'chromium-docker',
+      grep: /browser_navigate|browser_click/,
+      use: {
+        mcpBrowser: 'chromium',
+        mcpMode: 'docker' as const
+      }
+    }] : [],
     { name: 'firefox', use: { mcpBrowser: 'firefox' } },
     { name: 'webkit', use: { mcpBrowser: 'webkit' } },
+    { name: 'chromium-extension', use: { mcpBrowser: 'chromium', mcpMode: 'extension' } },
   ],
 });

src/browserContextFactory.ts

@@ -0,0 +1,266 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import fs from 'node:fs';
+import net from 'node:net';
+import path from 'node:path';
+import os from 'node:os';
+
+import debug from 'debug';
+import * as playwright from 'playwright';
+import { userDataDir } from './fileUtils.js';
+
+import type { FullConfig } from './config.js';
+import type { BrowserInfo, LaunchBrowserRequest } from './browserServer.js';
+
+const testDebug = debug('pw:mcp:test');
+
+export function contextFactory(browserConfig: FullConfig['browser']): BrowserContextFactory {
+  if (browserConfig.remoteEndpoint)
+    return new RemoteContextFactory(browserConfig);
+  if (browserConfig.cdpEndpoint)
+    return new CdpContextFactory(browserConfig);
+  if (browserConfig.isolated)
+    return new IsolatedContextFactory(browserConfig);
+  if (browserConfig.browserAgent)
+    return new BrowserServerContextFactory(browserConfig);
+  return new PersistentContextFactory(browserConfig);
+}
+
+export interface BrowserContextFactory {
+  createContext(): Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }>;
+}
+
+class BaseContextFactory implements BrowserContextFactory {
+  readonly browserConfig: FullConfig['browser'];
+  protected _browserPromise: Promise<playwright.Browser> | undefined;
+  readonly name: string;
+
+  constructor(name: string, browserConfig: FullConfig['browser']) {
+    this.name = name;
+    this.browserConfig = browserConfig;
+  }
+
+  protected async _obtainBrowser(): Promise<playwright.Browser> {
+    if (this._browserPromise)
+      return this._browserPromise;
+    testDebug(`obtain browser (${this.name})`);
+    this._browserPromise = this._doObtainBrowser();
+    void this._browserPromise.then(browser => {
+      browser.on('disconnected', () => {
+        this._browserPromise = undefined;
+      });
+    }).catch(() => {
+      this._browserPromise = undefined;
+    });
+    return this._browserPromise;
+  }
+
+  protected async _doObtainBrowser(): Promise<playwright.Browser> {
+    throw new Error('Not implemented');
+  }
+
+  async createContext(): Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }> {
+    testDebug(`create browser context (${this.name})`);
+    const browser = await this._obtainBrowser();
+    const browserContext = await this._doCreateContext(browser);
+    return { browserContext, close: () => this._closeBrowserContext(browserContext, browser) };
+  }
+
+  protected async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
+    throw new Error('Not implemented');
+  }
+
+  private async _closeBrowserContext(browserContext: playwright.BrowserContext, browser: playwright.Browser) {
+    testDebug(`close browser context (${this.name})`);
+    if (browser.contexts().length === 1)
+      this._browserPromise = undefined;
+    await browserContext.close().catch(() => {});
+    if (browser.contexts().length === 0) {
+      testDebug(`close browser (${this.name})`);
+      await browser.close().catch(() => {});
+    }
+  }
+}
+
+class IsolatedContextFactory extends BaseContextFactory {
+  constructor(browserConfig: FullConfig['browser']) {
+    super('isolated', browserConfig);
+  }
+
+  protected override async _doObtainBrowser(): Promise<playwright.Browser> {
+    await injectCdpPort(this.browserConfig);
+    const browserType = playwright[this.browserConfig.browserName];
+    return browserType.launch({
+      ...this.browserConfig.launchOptions,
+      handleSIGINT: false,
+      handleSIGTERM: false,
+    }).catch(error => {
+      if (error.message.includes('Executable doesn\'t exist'))
+        throw new Error(`Browser specified in your config is not installed. Either install it (likely) or change the config.`);
+      throw error;
+    });
+  }
+
+  protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
+    return browser.newContext(this.browserConfig.contextOptions);
+  }
+}
+
+class CdpContextFactory extends BaseContextFactory {
+  constructor(browserConfig: FullConfig['browser']) {
+    super('cdp', browserConfig);
+  }
+
+  protected override async _doObtainBrowser(): Promise<playwright.Browser> {
+    return playwright.chromium.connectOverCDP(this.browserConfig.cdpEndpoint!);
+  }
+
+  protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
+    return this.browserConfig.isolated ? await browser.newContext() : browser.contexts()[0];
+  }
+}
+
+class RemoteContextFactory extends BaseContextFactory {
+  constructor(browserConfig: FullConfig['browser']) {
+    super('remote', browserConfig);
+  }
+
+  protected override async _doObtainBrowser(): Promise<playwright.Browser> {
+    const url = new URL(this.browserConfig.remoteEndpoint!);
+    url.searchParams.set('browser', this.browserConfig.browserName);
+    if (this.browserConfig.launchOptions)
+      url.searchParams.set('launch-options', JSON.stringify(this.browserConfig.launchOptions));
+    return playwright[this.browserConfig.browserName].connect(String(url));
+  }
+
+  protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
+    return browser.newContext();
+  }
+}
+
+class PersistentContextFactory implements BrowserContextFactory {
+  readonly browserConfig: FullConfig['browser'];
+  private _userDataDirs = new Set<string>();
+
+  constructor(browserConfig: FullConfig['browser']) {
+    this.browserConfig = browserConfig;
+  }
+
+  async createContext(): Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }> {
+    await injectCdpPort(this.browserConfig);
+    testDebug('create browser context (persistent)');
+    const userDataDir = this.browserConfig.userDataDir ?? await this._createUserDataDir();
+
+    this._userDataDirs.add(userDataDir);
+    testDebug('lock user data dir', userDataDir);
+
+    const browserType = playwright[this.browserConfig.browserName];
+    for (let i = 0; i < 5; i++) {
+      try {
+        const browserContext = await browserType.launchPersistentContext(userDataDir, {
+          ...this.browserConfig.launchOptions,
+          ...this.browserConfig.contextOptions,
+          handleSIGINT: false,
+          handleSIGTERM: false,
+        });
+        const close = () => this._closeBrowserContext(browserContext, userDataDir);
+        return { browserContext, close };
+      } catch (error: any) {
+        if (error.message.includes('Executable doesn\'t exist'))
+          throw new Error(`Browser specified in your config is not installed. Either install it (likely) or change the config.`);
+        if (error.message.includes('ProcessSingleton') || error.message.includes('Invalid URL')) {
+          // User data directory is already in use, try again.
+          await new Promise(resolve => setTimeout(resolve, 1000));
+          continue;
+        }
+        throw error;
+      }
+    }
+    throw new Error(`Browser is already in use for ${userDataDir}, use --isolated to run multiple instances of the same browser`);
+  }
+
+  private async _closeBrowserContext(browserContext: playwright.BrowserContext, userDataDir: string) {
+    testDebug('close browser context (persistent)');
+    testDebug('release user data dir', userDataDir);
+    await browserContext.close().catch(() => {});
+    this._userDataDirs.delete(userDataDir);
+    testDebug('close browser context complete (persistent)');
+  }
+
+  private async _createUserDataDir() {
+    let cacheDirectory: string;
+    if (process.platform === 'linux')
+      cacheDirectory = process.env.XDG_CACHE_HOME || path.join(os.homedir(), '.cache');
+    else if (process.platform === 'darwin')
+      cacheDirectory = path.join(os.homedir(), 'Library', 'Caches');
+    else if (process.platform === 'win32')
+      cacheDirectory = process.env.LOCALAPPDATA || path.join(os.homedir(), 'AppData', 'Local');
+    else
+      throw new Error('Unsupported platform: ' + process.platform);
+    const result = path.join(cacheDirectory, 'ms-playwright', `mcp-${this.browserConfig.launchOptions?.channel ?? this.browserConfig?.browserName}-profile`);
+    await fs.promises.mkdir(result, { recursive: true });
+    return result;
+  }
+}
+
+export class BrowserServerContextFactory extends BaseContextFactory {
+  constructor(browserConfig: FullConfig['browser']) {
+    super('persistent', browserConfig);
+  }
+
+  protected override async _doObtainBrowser(): Promise<playwright.Browser> {
+    const response = await fetch(new URL(`/json/launch`, this.browserConfig.browserAgent), {
+      method: 'POST',
+      body: JSON.stringify({
+        browserType: this.browserConfig.browserName,
+        userDataDir: this.browserConfig.userDataDir ?? await this._createUserDataDir(),
+        launchOptions: this.browserConfig.launchOptions,
+        contextOptions: this.browserConfig.contextOptions,
+      } as LaunchBrowserRequest),
+    });
+    const info = await response.json() as BrowserInfo;
+    if (info.error)
+      throw new Error(info.error);
+    return await playwright.chromium.connectOverCDP(`http://localhost:${info.cdpPort}/`);
+  }
+
+  protected override async _doCreateContext(browser: playwright.Browser): Promise<playwright.BrowserContext> {
+    return this.browserConfig.isolated ? await browser.newContext() : browser.contexts()[0];
+  }
+
+  private async _createUserDataDir() {
+    const dir = await userDataDir(this.browserConfig);
+    await fs.promises.mkdir(dir, { recursive: true });
+    return dir;
+  }
+}
+
+async function injectCdpPort(browserConfig: FullConfig['browser']) {
+  if (browserConfig.browserName === 'chromium')
+    (browserConfig.launchOptions as any).cdpPort = await findFreePort();
+}
+
+async function findFreePort() {
+  return new Promise((resolve, reject) => {
+    const server = net.createServer();
+    server.listen(0, () => {
+      const { port } = server.address() as net.AddressInfo;
+      server.close(() => resolve(port));
+    });
+    server.on('error', reject);
+  });
+}

src/browserServer.ts

@@ -0,0 +1,197 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* eslint-disable no-console */
+
+import net from 'net';
+
+import { program } from 'commander';
+import playwright from 'playwright';
+
+import { HttpServer } from './httpServer.js';
+import { packageJSON } from './package.js';
+
+import type http from 'http';
+
+export type LaunchBrowserRequest = {
+  browserType: string;
+  userDataDir: string;
+  launchOptions: playwright.LaunchOptions;
+  contextOptions: playwright.BrowserContextOptions;
+};
+
+export type BrowserInfo = {
+  browserType: string;
+  userDataDir: string;
+  cdpPort: number;
+  launchOptions: playwright.LaunchOptions;
+  contextOptions: playwright.BrowserContextOptions;
+  error?: string;
+};
+
+type BrowserEntry = {
+  browser?: playwright.Browser;
+  info: BrowserInfo;
+};
+
+class BrowserServer {
+  private _server = new HttpServer();
+  private _entries: BrowserEntry[] = [];
+
+  constructor() {
+    this._setupExitHandler();
+  }
+
+  async start(port: number) {
+    await this._server.start({ port });
+    this._server.routePath('/json/list', (req, res) => {
+      this._handleJsonList(res);
+    });
+    this._server.routePath('/json/launch', async (req, res) => {
+      void this._handleLaunchBrowser(req, res).catch(e => console.error(e));
+    });
+    this._setEntries([]);
+  }
+
+  private _handleJsonList(res: http.ServerResponse) {
+    const list = this._entries.map(browser => browser.info);
+    res.end(JSON.stringify(list));
+  }
+
+  private async _handleLaunchBrowser(req: http.IncomingMessage, res: http.ServerResponse) {
+    const request = await readBody<LaunchBrowserRequest>(req);
+    let info = this._entries.map(entry => entry.info).find(info => info.userDataDir === request.userDataDir);
+    if (!info || info.error)
+      info = await this._newBrowser(request);
+    res.end(JSON.stringify(info));
+  }
+
+  private async _newBrowser(request: LaunchBrowserRequest): Promise<BrowserInfo> {
+    const cdpPort = await findFreePort();
+    (request.launchOptions as any).cdpPort = cdpPort;
+    const info: BrowserInfo = {
+      browserType: request.browserType,
+      userDataDir: request.userDataDir,
+      cdpPort,
+      launchOptions: request.launchOptions,
+      contextOptions: request.contextOptions,
+    };
+
+    const browserType = playwright[request.browserType as 'chromium' | 'firefox' | 'webkit'];
+    const { browser, error } = await browserType.launchPersistentContext(request.userDataDir, {
+      ...request.launchOptions,
+      ...request.contextOptions,
+      handleSIGINT: false,
+      handleSIGTERM: false,
+    }).then(context => {
+      return { browser: context.browser()!, error: undefined };
+    }).catch(error => {
+      return { browser: undefined, error: error.message };
+    });
+    this._setEntries([...this._entries, {
+      browser,
+      info: {
+        browserType: request.browserType,
+        userDataDir: request.userDataDir,
+        cdpPort,
+        launchOptions: request.launchOptions,
+        contextOptions: request.contextOptions,
+        error,
+      },
+    }]);
+    browser?.on('disconnected', () => {
+      this._setEntries(this._entries.filter(entry => entry.browser !== browser));
+    });
+    return info;
+  }
+
+  private _updateReport() {
+    // Clear the current line and move cursor to top of screen
+    process.stdout.write('\x1b[2J\x1b[H');
+    process.stdout.write(`Playwright Browser Server v${packageJSON.version}\n`);
+    process.stdout.write(`Listening on ${this._server.urlPrefix('human-readable')}\n\n`);
+
+    if (this._entries.length === 0) {
+      process.stdout.write('No browsers currently running\n');
+      return;
+    }
+
+    process.stdout.write('Running browsers:\n');
+    for (const entry of this._entries) {
+      const status = entry.browser ? 'running' : 'error';
+      const statusColor = entry.browser ? '\x1b[32m' : '\x1b[31m'; // green for running, red for error
+      process.stdout.write(`${statusColor}${entry.info.browserType}\x1b[0m (${entry.info.userDataDir}) - ${statusColor}${status}\x1b[0m\n`);
+      if (entry.info.error)
+        process.stdout.write(`  Error: ${entry.info.error}\n`);
+    }
+
+  }
+
+  private _setEntries(entries: BrowserEntry[]) {
+    this._entries = entries;
+    this._updateReport();
+  }
+
+  private _setupExitHandler() {
+    let isExiting = false;
+    const handleExit = async () => {
+      if (isExiting)
+        return;
+      isExiting = true;
+      setTimeout(() => process.exit(0), 15000);
+      for (const entry of this._entries)
+        await entry.browser?.close().catch(() => {});
+      process.exit(0);
+    };
+
+    process.stdin.on('close', handleExit);
+    process.on('SIGINT', handleExit);
+    process.on('SIGTERM', handleExit);
+  }
+}
+
+program
+    .name('browser-agent')
+    .option('-p, --port <port>', 'Port to listen on', '9224')
+    .action(async options => {
+      await main(options);
+    });
+
+void program.parseAsync(process.argv);
+
+async function main(options: { port: string }) {
+  const server = new BrowserServer();
+  await server.start(+options.port);
+}
+
+function readBody<T>(req: http.IncomingMessage): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const chunks: Buffer[] = [];
+    req.on('data', (chunk: Buffer) => chunks.push(chunk));
+    req.on('end', () => resolve(JSON.parse(Buffer.concat(chunks).toString())));
+  });
+}
+
+async function findFreePort(): Promise<number> {
+  return new Promise((resolve, reject) => {
+    const server = net.createServer();
+    server.listen(0, () => {
+      const { port } = server.address() as net.AddressInfo;
+      server.close(() => resolve(port));
+    });
+    server.on('error', reject);
+  });
+}

src/cdpRelay.ts

@@ -0,0 +1,317 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Bridge Server - Standalone WebSocket server that bridges Playwright MCP and Chrome Extension
+ *
+ * Endpoints:
+ * - /cdp - Full CDP interface for Playwright MCP
+ * - /extension - Extension connection for chrome.debugger forwarding
+ */
+
+/* eslint-disable no-console */
+
+import { WebSocket, WebSocketServer } from 'ws';
+import http from 'node:http';
+import { EventEmitter } from 'node:events';
+import debug from 'debug';
+import { httpAddressToString } from './transport.js';
+
+const debugLogger = debug('pw:mcp:relay');
+
+const CDP_PATH = '/cdp';
+const EXTENSION_PATH = '/extension';
+
+export class CDPRelayServer extends EventEmitter {
+  private _wss: WebSocketServer;
+  private _playwrightSocket: WebSocket | null = null;
+  private _extensionSocket: WebSocket | null = null;
+  private _connectionInfo: {
+    targetInfo: any;
+    sessionId: string;
+  } | undefined;
+
+  constructor(server: http.Server) {
+    super();
+    this._wss = new WebSocketServer({ server });
+    this._wss.on('connection', this._onConnection.bind(this));
+  }
+
+  stop(): void {
+    this._playwrightSocket?.close();
+    this._extensionSocket?.close();
+  }
+
+  private _onConnection(ws: WebSocket, request: http.IncomingMessage): void {
+    const url = new URL(`http://localhost${request.url}`);
+
+    debugLogger(`New connection to ${url.pathname}`);
+
+    if (url.pathname === CDP_PATH) {
+      this._handlePlaywrightConnection(ws);
+    } else if (url.pathname === EXTENSION_PATH) {
+      this._handleExtensionConnection(ws);
+    } else {
+      debugLogger(`Invalid path: ${url.pathname}`);
+      ws.close(4004, 'Invalid path');
+    }
+  }
+
+  /**
+   * Handle Playwright MCP connection - provides full CDP interface
+   */
+  private _handlePlaywrightConnection(ws: WebSocket): void {
+    if (this._playwrightSocket?.readyState === WebSocket.OPEN) {
+      debugLogger('Closing previous Playwright connection');
+      this._playwrightSocket.close(1000, 'New connection established');
+    }
+
+    this._playwrightSocket = ws;
+    debugLogger('Playwright MCP connected');
+
+    ws.on('message', data => {
+      try {
+        const message = JSON.parse(data.toString());
+        this._handlePlaywrightMessage(message);
+      } catch (error) {
+        debugLogger('Error parsing Playwright message:', error);
+      }
+    });
+
+    ws.on('close', () => {
+      if (this._playwrightSocket === ws)
+        this._playwrightSocket = null;
+
+      debugLogger('Playwright MCP disconnected');
+    });
+
+    ws.on('error', error => {
+      debugLogger('Playwright WebSocket error:', error);
+    });
+  }
+
+  /**
+   * Handle Extension connection - forwards to chrome.debugger
+   */
+  private _handleExtensionConnection(ws: WebSocket): void {
+    if (this._extensionSocket?.readyState === WebSocket.OPEN) {
+      debugLogger('Closing previous extension connection');
+      this._extensionSocket.close(1000, 'New connection established');
+    }
+
+    this._extensionSocket = ws;
+    debugLogger('Extension connected');
+
+    ws.on('message', data => {
+      try {
+        const message = JSON.parse(data.toString());
+        this._handleExtensionMessage(message);
+      } catch (error) {
+        debugLogger('Error parsing extension message:', error);
+      }
+    });
+
+    ws.on('close', () => {
+      if (this._extensionSocket === ws)
+        this._extensionSocket = null;
+
+      debugLogger('Extension disconnected');
+    });
+
+    ws.on('error', error => {
+      debugLogger('Extension WebSocket error:', error);
+    });
+  }
+
+  /**
+   * Handle messages from Playwright MCP
+   */
+  private _handlePlaywrightMessage(message: any): void {
+    debugLogger('← Playwright:', message.method || `response(${message.id})`);
+
+    // Handle Browser domain methods locally
+    if (message.method?.startsWith('Browser.')) {
+      this._handleBrowserDomainMethod(message);
+      return;
+    }
+
+    // Handle Target domain methods
+    if (message.method?.startsWith('Target.')) {
+      this._handleTargetDomainMethod(message);
+      return;
+    }
+
+    // Forward other commands to extension
+    if (message.method)
+      this._forwardToExtension(message);
+
+  }
+
+  /**
+   * Handle messages from Extension
+   */
+  private _handleExtensionMessage(message: any): void {
+    // Handle connection info from extension
+    if (message.type === 'connection_info') {
+      debugLogger('← Extension connected to tab:', message);
+      this._connectionInfo = {
+        targetInfo: message.targetInfo,
+        // Page sessionId that should be used by this connection.
+        sessionId: message.sessionId
+      };
+      return;
+    }
+
+    // CDP event from extension
+    debugLogger(`← Extension message: ${message.method ?? (message.id && `response(id=${message.id})`) ?? 'unknown'}`);
+    this._sendToPlaywright(message);
+  }
+
+  /**
+   * Handle Browser domain methods locally
+   */
+  private _handleBrowserDomainMethod(message: any): void {
+    switch (message.method) {
+      case 'Browser.getVersion':
+        this._sendToPlaywright({
+          id: message.id,
+          result: {
+            protocolVersion: '1.3',
+            product: 'Chrome/Extension-Bridge',
+            userAgent: 'CDP-Bridge-Server/1.0.0',
+          }
+        });
+        break;
+
+      case 'Browser.setDownloadBehavior':
+        this._sendToPlaywright({
+          id: message.id,
+          result: {}
+        });
+        break;
+
+      default:
+        // Forward unknown Browser methods to extension
+        this._forwardToExtension(message);
+    }
+  }
+
+  /**
+   * Handle Target domain methods
+   */
+  private _handleTargetDomainMethod(message: any): void {
+    switch (message.method) {
+      case 'Target.setAutoAttach':
+        // Simulate auto-attach behavior with real target info
+        if (this._connectionInfo && !message.sessionId) {
+          debugLogger('Simulating auto-attach for target:', JSON.stringify(message));
+          this._sendToPlaywright({
+            method: 'Target.attachedToTarget',
+            params: {
+              sessionId: this._connectionInfo.sessionId,
+              targetInfo: {
+                ...this._connectionInfo.targetInfo,
+                attached: true,
+              },
+              waitingForDebugger: false
+            }
+          });
+          this._sendToPlaywright({
+            id: message.id,
+            result: {}
+          });
+        } else {
+          this._forwardToExtension(message);
+        }
+        break;
+
+      case 'Target.getTargets':
+        const targetInfos = [];
+
+        if (this._connectionInfo) {
+          targetInfos.push({
+            ...this._connectionInfo.targetInfo,
+            attached: true,
+          });
+        }
+
+        this._sendToPlaywright({
+          id: message.id,
+          result: { targetInfos }
+        });
+        break;
+
+      default:
+        this._forwardToExtension(message);
+    }
+  }
+
+  /**
+   * Forward message to extension
+   */
+  private _forwardToExtension(message: any): void {
+    if (this._extensionSocket?.readyState === WebSocket.OPEN) {
+      debugLogger('→ Extension:', message.method || `command(${message.id})`);
+      this._extensionSocket.send(JSON.stringify(message));
+    } else {
+      debugLogger('Extension not connected, cannot forward message');
+      if (message.id) {
+        this._sendToPlaywright({
+          id: message.id,
+          error: { message: 'Extension not connected' }
+        });
+      }
+    }
+  }
+
+  /**
+   * Forward message to Playwright
+   */
+  private _sendToPlaywright(message: any): void {
+    if (this._playwrightSocket?.readyState === WebSocket.OPEN) {
+      debugLogger('→ Playwright:', JSON.stringify(message));
+      this._playwrightSocket.send(JSON.stringify(message));
+    }
+  }
+}
+
+export async function startCDPRelayServer(httpServer: http.Server) {
+  const wsAddress = httpAddressToString(httpServer.address()).replace(/^http/, 'ws');
+  const cdpRelayServer = new CDPRelayServer(httpServer);
+  process.on('exit', () => cdpRelayServer.stop());
+  // eslint-disable-next-line no-console
+  console.error(`CDP relay server started on ${wsAddress}${EXTENSION_PATH} - Connect to it using the browser extension.`);
+  const cdpEndpoint = `${wsAddress}${CDP_PATH}`;
+  return cdpEndpoint;
+}
+
+// CLI usage
+if (import.meta.url === `file://${process.argv[1]}`) {
+  const port = parseInt(process.argv[2], 10) || 9223;
+  const httpServer = http.createServer();
+  await new Promise<void>(resolve => httpServer.listen(port, resolve));
+  const server = new CDPRelayServer(httpServer);
+
+  console.error(`CDP Bridge Server listening on ws://localhost:${port}`);
+  console.error(`- Playwright MCP: ws://localhost:${port}${CDP_PATH}`);
+  console.error(`- Extension: ws://localhost:${port}${EXTENSION_PATH}`);
+
+  process.on('SIGINT', () => {
+    debugLogger('\nShutting down bridge server...');
+    server.stop();
+    process.exit(0);
+  });
+}

src/config.ts

@@ -15,20 +15,28 @@
  */
 
 import fs from 'fs';
-import net from 'net';
 import os from 'os';
 import path from 'path';
 import { devices } from 'playwright';
 
-import type { Config, ToolCapability } from '../config.js';
+import type { Config as PublicConfig, ToolCapability } from '../config.js';
 import type { BrowserContextOptions, LaunchOptions } from 'playwright';
 import { sanitizeForFilePath } from './tools/utils.js';
 
+type Config = PublicConfig & {
+  /**
+   * TODO: Move to PublicConfig once we are ready to release this feature.
+   * Run server that is able to connect to the 'Playwright MCP' Chrome extension.
+   */
+  extension?: boolean;
+};
+
 export type CLIOptions = {
   allowedOrigins?: string[];
   blockedOrigins?: string[];
   blockServiceWorkers?: boolean;
   browser?: string;
+  browserAgent?: string;
   caps?: string;
   cdpEndpoint?: string;
   config?: string;
@@ -38,20 +46,22 @@ export type CLIOptions = {
   host?: string;
   ignoreHttpsErrors?: boolean;
   isolated?: boolean;
-  imageResponses: boolean;
+  imageResponses?: 'allow' | 'omit' | 'auto';
   sandbox: boolean;
   outputDir?: string;
   port?: number;
   proxyBypass?: string;
   proxyServer?: string;
+  saveTrace?: boolean;
   storageState?: string;
   userAgent?: string;
   userDataDir?: string;
   viewportSize?: string;
   vision?: boolean;
+  extension?: boolean;
 };
 
-const defaultConfig: Config = {
+const defaultConfig: FullConfig = {
   browser: {
     browserName: 'chromium',
     launchOptions: {
@@ -67,16 +77,46 @@ const defaultConfig: Config = {
     allowedOrigins: undefined,
     blockedOrigins: undefined,
   },
+  server: {},
+  outputDir: path.join(os.tmpdir(), 'playwright-mcp-output', sanitizeForFilePath(new Date().toISOString())),
 };
 
-export async function resolveConfig(cliOptions: CLIOptions): Promise<Config> {
-  const config = await loadConfig(cliOptions.config);
+type BrowserUserConfig = NonNullable<Config['browser']>;
+
+export type FullConfig = Config & {
+  browser: Omit<BrowserUserConfig, 'browserName'> & {
+    browserName: 'chromium' | 'firefox' | 'webkit';
+    launchOptions: NonNullable<BrowserUserConfig['launchOptions']>;
+    contextOptions: NonNullable<BrowserUserConfig['contextOptions']>;
+  },
+  network: NonNullable<Config['network']>,
+  outputDir: string;
+  server: NonNullable<Config['server']>,
+};
+
+export async function resolveConfig(config: Config): Promise<FullConfig> {
+  return mergeConfig(defaultConfig, config);
+}
+
+export async function resolveCLIConfig(cliOptions: CLIOptions): Promise<FullConfig> {
+  const configInFile = await loadConfig(cliOptions.config);
   const cliOverrides = await configFromCLIOptions(cliOptions);
-  return mergeConfig(defaultConfig, mergeConfig(config, cliOverrides));
+  const result = mergeConfig(mergeConfig(defaultConfig, configInFile), cliOverrides);
+  // Derive artifact output directory from config.outputDir
+  if (result.saveTrace)
+    result.browser.launchOptions.tracesDir = path.join(result.outputDir, 'traces');
+  return result;
+}
+
+export function validateConfig(config: Config) {
+  if (config.extension) {
+    if (config.browser?.browserName !== 'chromium')
+      throw new Error('Extension mode is only supported for Chromium browsers.');
+  }
 }
 
 export async function configFromCLIOptions(cliOptions: CLIOptions): Promise<Config> {
-  let browserName: 'chromium' | 'firefox' | 'webkit';
+  let browserName: 'chromium' | 'firefox' | 'webkit' | undefined;
   let channel: string | undefined;
   switch (cliOptions.browser) {
     case 'chrome':
@@ -97,9 +137,6 @@ export async function configFromCLIOptions(cliOptions: CLIOptions): Promise<Conf
     case 'webkit':
       browserName = 'webkit';
       break;
-    default:
-      browserName = 'chromium';
-      channel = 'chrome';
   }
 
   // Launch options
@@ -109,13 +146,9 @@ export async function configFromCLIOptions(cliOptions: CLIOptions): Promise<Conf
     headless: cliOptions.headless,
   };
 
-  if (browserName === 'chromium') {
-    (launchOptions as any).cdpPort = await findFreePort();
-    if (!cliOptions.sandbox) {
-      // --no-sandbox was passed, disable the sandbox
-      launchOptions.chromiumSandbox = false;
-    }
-  }
+  // --no-sandbox was passed, disable the sandbox
+  if (!cliOptions.sandbox)
+    launchOptions.chromiumSandbox = false;
 
   if (cliOptions.proxyServer) {
     launchOptions.proxy = {
@@ -125,6 +158,11 @@ export async function configFromCLIOptions(cliOptions: CLIOptions): Promise<Conf
       launchOptions.proxy.bypass = cliOptions.proxyBypass;
   }
 
+  if (cliOptions.device && cliOptions.cdpEndpoint)
+    throw new Error('Device emulation is not supported with cdpEndpoint.');
+  if (cliOptions.device && cliOptions.extension)
+    throw new Error('Device emulation is not supported with extension mode.');
+
   // Context options
   const contextOptions: BrowserContextOptions = cliOptions.device ? devices[cliOptions.device] : {};
   if (cliOptions.storageState)
@@ -152,6 +190,7 @@ export async function configFromCLIOptions(cliOptions: CLIOptions): Promise<Conf
 
   const result: Config = {
     browser: {
+      browserAgent: cliOptions.browserAgent ?? process.env.PW_BROWSER_AGENT,
       browserName,
       isolated: cliOptions.isolated,
       userDataDir: cliOptions.userDataDir,
@@ -165,32 +204,19 @@ export async function configFromCLIOptions(cliOptions: CLIOptions): Promise<Conf
     },
     capabilities: cliOptions.caps?.split(',').map((c: string) => c.trim() as ToolCapability),
     vision: !!cliOptions.vision,
+    extension: !!cliOptions.extension,
     network: {
       allowedOrigins: cliOptions.allowedOrigins,
       blockedOrigins: cliOptions.blockedOrigins,
     },
+    saveTrace: cliOptions.saveTrace,
     outputDir: cliOptions.outputDir,
+    imageResponses: cliOptions.imageResponses,
   };
 
-  if (!cliOptions.imageResponses) {
-    // --no-image-responses was passed, disable image responses
-    result.noImageResponses = true;
-  }
-
   return result;
 }
 
-async function findFreePort() {
-  return new Promise((resolve, reject) => {
-    const server = net.createServer();
-    server.listen(0, () => {
-      const { port } = server.address() as net.AddressInfo;
-      server.close(() => resolve(port));
-    });
-    server.on('error', reject);
-  });
-}
-
 async function loadConfig(configFile: string | undefined): Promise<Config> {
   if (!configFile)
     return {};
@@ -202,11 +228,10 @@ async function loadConfig(configFile: string | undefined): Promise<Config> {
   }
 }
 
-export async function outputFile(config: Config, name: string): Promise<string> {
-  const result = config.outputDir ?? os.tmpdir();
-  await fs.promises.mkdir(result, { recursive: true });
+export async function outputFile(config: FullConfig, name: string): Promise<string> {
+  await fs.promises.mkdir(config.outputDir, { recursive: true });
   const fileName = sanitizeForFilePath(name);
-  return path.join(result, fileName);
+  return path.join(config.outputDir, fileName);
 }
 
 function pickDefined<T extends object>(obj: T | undefined): Partial<T> {
@@ -215,10 +240,12 @@ function pickDefined<T extends object>(obj: T | undefined): Partial<T> {
   ) as Partial<T>;
 }
 
-function mergeConfig(base: Config, overrides: Config): Config {
-  const browser: Config['browser'] = {
+function mergeConfig(base: FullConfig, overrides: Config): FullConfig {
+  const browser: FullConfig['browser'] = {
     ...pickDefined(base.browser),
     ...pickDefined(overrides.browser),
+    browserName: overrides.browser?.browserName ?? base.browser?.browserName ?? 'chromium',
+    isolated: overrides.browser?.isolated ?? base.browser?.isolated ?? false,
     launchOptions: {
       ...pickDefined(base.browser?.launchOptions),
       ...pickDefined(overrides.browser?.launchOptions),
@@ -241,5 +268,9 @@ function mergeConfig(base: Config, overrides: Config): Config {
       ...pickDefined(base.network),
       ...pickDefined(overrides.network),
     },
-  };
+    server: {
+      ...pickDefined(base.server),
+      ...pickDefined(overrides.server),
+    },
+  } as FullConfig;
 }

src/connection.ts

@@ -14,22 +14,24 @@
  * limitations under the License.
  */
 
-import { Server } from '@modelcontextprotocol/sdk/server/index.js';
+import { Server as McpServer } from '@modelcontextprotocol/sdk/server/index.js';
 import { CallToolRequestSchema, ListToolsRequestSchema, Tool as McpTool } from '@modelcontextprotocol/sdk/types.js';
 import { zodToJsonSchema } from 'zod-to-json-schema';
 
-import { Context, packageJSON } from './context.js';
+import { Context } from './context.js';
 import { snapshotTools, visionTools } from './tools.js';
+import { packageJSON } from './package.js';
 
-import type { Config } from '../config.js';
-import type { Transport } from '@modelcontextprotocol/sdk/shared/transport.js';
+import { FullConfig, validateConfig } from './config.js';
 
-export async function createConnection(config: Config): Promise<Connection> {
+import type { BrowserContextFactory } from './browserContextFactory.js';
+
+export function createConnection(config: FullConfig, browserContextFactory: BrowserContextFactory): Connection {
   const allTools = config.vision ? visionTools : snapshotTools;
   const tools = allTools.filter(tool => !config.capabilities || tool.capability === 'core' || config.capabilities.includes(tool.capability));
-
-  const context = new Context(tools, config);
-  const server = new Server({ name: 'Playwright', version: packageJSON.version }, {
+  validateConfig(config);
+  const context = new Context(tools, config, browserContextFactory);
+  const server = new McpServer({ name: 'Playwright', version: packageJSON.version }, {
     capabilities: {
       tools: {},
     }
@@ -74,26 +76,19 @@ export async function createConnection(config: Config): Promise<Connection> {
     }
   });
 
-  const connection = new Connection(server, context);
-  return connection;
+  return new Connection(server, context);
 }
 
 export class Connection {
-  readonly server: Server;
+  readonly server: McpServer;
   readonly context: Context;
 
-  constructor(server: Server, context: Context) {
+  constructor(server: McpServer, context: Context) {
     this.server = server;
     this.context = context;
-  }
-
-  async connect(transport: Transport) {
-    await this.server.connect(transport);
-    await new Promise<void>(resolve => {
-      this.server.oninitialized = () => resolve();
-    });
-    if (this.server.getClientVersion()?.name.includes('cursor'))
-      this.context.config.noImageResponses = true;
+    this.server.oninitialized = () => {
+      this.context.clientVersion = this.server.getClientVersion();
+    };
   }
 
   async close() {

src/context.ts

@@ -14,44 +14,50 @@
  * limitations under the License.
  */
 
-import fs from 'node:fs';
-import url from 'node:url';
-import os from 'node:os';
-import path from 'node:path';
-
+import debug from 'debug';
 import * as playwright from 'playwright';
 
-import { waitForCompletion } from './tools/utils.js';
+import { callOnPageNoTrace, waitForCompletion } from './tools/utils.js';
 import { ManualPromise } from './manualPromise.js';
 import { Tab } from './tab.js';
+import { outputFile } from './config.js';
 
 import type { ImageContent, TextContent } from '@modelcontextprotocol/sdk/types.js';
 import type { ModalState, Tool, ToolActionResult } from './tools/tool.js';
-import type { Config } from '../config.js';
-import { outputFile } from './config.js';
+import type { FullConfig } from './config.js';
+import type { BrowserContextFactory } from './browserContextFactory.js';
 
 type PendingAction = {
   dialogShown: ManualPromise<void>;
 };
 
-type BrowserContextAndBrowser = {
-  browser?: playwright.Browser;
-  browserContext: playwright.BrowserContext;
-};
+const testDebug = debug('pw:mcp:test');
 
 export class Context {
   readonly tools: Tool[];
-  readonly config: Config;
-  private _browserContextPromise: Promise<BrowserContextAndBrowser> | undefined;
+  readonly config: FullConfig;
+  private _browserContextPromise: Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }> | undefined;
+  private _browserContextFactory: BrowserContextFactory;
   private _tabs: Tab[] = [];
   private _currentTab: Tab | undefined;
   private _modalStates: (ModalState & { tab: Tab })[] = [];
   private _pendingAction: PendingAction | undefined;
   private _downloads: { download: playwright.Download, finished: boolean, outputFile: string }[] = [];
+  clientVersion: { name: string; version: string; } | undefined;
 
-  constructor(tools: Tool[], config: Config) {
+  constructor(tools: Tool[], config: FullConfig, browserContextFactory: BrowserContextFactory) {
     this.tools = tools;
     this.config = config;
+    this._browserContextFactory = browserContextFactory;
+    testDebug('create context');
+  }
+
+  clientSupportsImages(): boolean {
+    if (this.config.imageResponses === 'allow')
+      return true;
+    if (this.config.imageResponses === 'omit')
+      return false;
+    return !this.clientVersion?.name.includes('cursor');
   }
 
   modalStates(): ModalState[] {
@@ -83,7 +89,7 @@ export class Context {
 
   currentTabOrDie(): Tab {
     if (!this._currentTab)
-      throw new Error('No current snapshot available. Capture a snapshot of navigate to a new location first.');
+      throw new Error('No current snapshot available. Capture a snapshot or navigate to a new location first.');
     return this._currentTab;
   }
 
@@ -112,7 +118,7 @@ export class Context {
     const lines: string[] = ['### Open tabs'];
     for (let i = 0; i < this._tabs.length; i++) {
       const tab = this._tabs[i];
-      const title = await tab.page.title();
+      const title = await tab.title();
       const url = tab.page.url();
       const current = tab === this._currentTab ? ' (current)' : '';
       lines.push(`- ${i + 1}:${current} [${title}] (${url})`);
@@ -149,7 +155,7 @@ export class Context {
     let actionResult: { content?: (ImageContent | TextContent)[] } | undefined;
     try {
       if (waitForNetwork)
-        actionResult = await waitForCompletion(this, tab.page, async () => racingAction?.()) ?? undefined;
+        actionResult = await waitForCompletion(this, tab, async () => racingAction?.()) ?? undefined;
       else
         actionResult = await racingAction?.() ?? undefined;
     } finally {
@@ -193,7 +199,7 @@ ${code.join('\n')}
 
     result.push(
         `- Page URL: ${tab.page.url()}`,
-        `- Page Title: ${await tab.page.title()}`
+        `- Page Title: ${await tab.title()}`
     );
 
     if (captureSnapshot && tab.hasSnapshot())
@@ -213,10 +219,14 @@ ${code.join('\n')}
   }
 
   async waitForTimeout(time: number) {
-    if (this._currentTab && !this._javaScriptBlocked())
-      await this._currentTab.page.evaluate(() => new Promise(f => setTimeout(f, 1000)));
-    else
+    if (!this._currentTab || this._javaScriptBlocked()) {
       await new Promise(f => setTimeout(f, time));
+      return;
+    }
+
+    await callOnPageNoTrace(this._currentTab.page, page => {
+      return page.evaluate(() => new Promise(f => setTimeout(f, 1000)));
+    });
   }
 
   private async _raceAgainstModalDialogs(action: () => Promise<ToolActionResult>): Promise<ToolActionResult> {
@@ -284,13 +294,15 @@ ${code.join('\n')}
     if (!this._browserContextPromise)
       return;
 
+    testDebug('close context');
+
     const promise = this._browserContextPromise;
     this._browserContextPromise = undefined;
 
-    await promise.then(async ({ browserContext, browser }) => {
-      await browserContext.close().then(async () => {
-        await browser?.close();
-      }).catch(() => {});
+    await promise.then(async ({ browserContext, close }) => {
+      if (this.config.saveTrace)
+        await browserContext.tracing.stop();
+      await close();
     });
   }
 
@@ -318,85 +330,22 @@ ${code.join('\n')}
     return this._browserContextPromise;
   }
 
-  private async _setupBrowserContext(): Promise<BrowserContextAndBrowser> {
-    const { browser, browserContext } = await this._createBrowserContext();
+  private async _setupBrowserContext(): Promise<{ browserContext: playwright.BrowserContext, close: () => Promise<void> }> {
+    // TODO: move to the browser context factory to make it based on isolation mode.
+    const result = await this._browserContextFactory.createContext();
+    const { browserContext } = result;
     await this._setupRequestInterception(browserContext);
     for (const page of browserContext.pages())
       this._onPageCreated(page);
     browserContext.on('page', page => this._onPageCreated(page));
-    return { browser, browserContext };
-  }
-
-  private async _createBrowserContext(): Promise<BrowserContextAndBrowser> {
-    if (this.config.browser?.remoteEndpoint) {
-      const url = new URL(this.config.browser?.remoteEndpoint);
-      if (this.config.browser.browserName)
-        url.searchParams.set('browser', this.config.browser.browserName);
-      if (this.config.browser.launchOptions)
-        url.searchParams.set('launch-options', JSON.stringify(this.config.browser.launchOptions));
-      const browser = await playwright[this.config.browser?.browserName ?? 'chromium'].connect(String(url));
-      const browserContext = await browser.newContext();
-      return { browser, browserContext };
+    if (this.config.saveTrace) {
+      await browserContext.tracing.start({
+        name: 'trace',
+        screenshots: false,
+        snapshots: true,
+        sources: false,
+      });
     }
-
-    if (this.config.browser?.cdpEndpoint) {
-      const browser = await playwright.chromium.connectOverCDP(this.config.browser.cdpEndpoint);
-      const browserContext = this.config.browser.isolated ? await browser.newContext() : browser.contexts()[0];
-      return { browser, browserContext };
-    }
-
-    return this.config.browser?.isolated ?
-      await createIsolatedContext(this.config.browser) :
-      await launchPersistentContext(this.config.browser);
+    return result;
   }
 }
-
-async function createIsolatedContext(browserConfig: Config['browser']): Promise<BrowserContextAndBrowser> {
-  try {
-    const browserName = browserConfig?.browserName ?? 'chromium';
-    const browserType = playwright[browserName];
-    const browser = await browserType.launch(browserConfig?.launchOptions);
-    const browserContext = await browser.newContext(browserConfig?.contextOptions);
-    return { browser, browserContext };
-  } catch (error: any) {
-    if (error.message.includes('Executable doesn\'t exist'))
-      throw new Error(`Browser specified in your config is not installed. Either install it (likely) or change the config.`);
-    throw error;
-  }
-}
-
-async function launchPersistentContext(browserConfig: Config['browser']): Promise<BrowserContextAndBrowser> {
-  try {
-    const browserName = browserConfig?.browserName ?? 'chromium';
-    const userDataDir = browserConfig?.userDataDir ?? await createUserDataDir({ ...browserConfig, browserName });
-    const browserType = playwright[browserName];
-    const browserContext = await browserType.launchPersistentContext(userDataDir, { ...browserConfig?.launchOptions, ...browserConfig?.contextOptions });
-    return { browserContext };
-  } catch (error: any) {
-    if (error.message.includes('Executable doesn\'t exist'))
-      throw new Error(`Browser specified in your config is not installed. Either install it (likely) or change the config.`);
-    throw error;
-  }
-}
-
-async function createUserDataDir(browserConfig: Config['browser']) {
-  let cacheDirectory: string;
-  if (process.platform === 'linux')
-    cacheDirectory = process.env.XDG_CACHE_HOME || path.join(os.homedir(), '.cache');
-  else if (process.platform === 'darwin')
-    cacheDirectory = path.join(os.homedir(), 'Library', 'Caches');
-  else if (process.platform === 'win32')
-    cacheDirectory = process.env.LOCALAPPDATA || path.join(os.homedir(), 'AppData', 'Local');
-  else
-    throw new Error('Unsupported platform: ' + process.platform);
-  const result = path.join(cacheDirectory, 'ms-playwright', `mcp-${browserConfig?.launchOptions?.channel ?? browserConfig?.browserName}-profile`);
-  await fs.promises.mkdir(result, { recursive: true });
-  return result;
-}
-
-export async function generateLocator(locator: playwright.Locator): Promise<string> {
-  return (locator as any)._generateLocatorString();
-}
-
-const __filename = url.fileURLToPath(import.meta.url);
-export const packageJSON = JSON.parse(fs.readFileSync(path.join(path.dirname(__filename), '..', 'package.json'), 'utf8'));

src/fileUtils.ts

@@ -0,0 +1,37 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import os from 'node:os';
+import path from 'node:path';
+
+import type { FullConfig } from './config.js';
+
+export function cacheDir() {
+  let cacheDirectory: string;
+  if (process.platform === 'linux')
+    cacheDirectory = process.env.XDG_CACHE_HOME || path.join(os.homedir(), '.cache');
+  else if (process.platform === 'darwin')
+    cacheDirectory = path.join(os.homedir(), 'Library', 'Caches');
+  else if (process.platform === 'win32')
+    cacheDirectory = process.env.LOCALAPPDATA || path.join(os.homedir(), 'AppData', 'Local');
+  else
+    throw new Error('Unsupported platform: ' + process.platform);
+  return path.join(cacheDirectory, 'ms-playwright');
+}
+
+export async function userDataDir(browserConfig: FullConfig['browser']) {
+  return path.join(cacheDir(), 'ms-playwright', `mcp-${browserConfig.launchOptions?.channel ?? browserConfig?.browserName}-profile`);
+}

src/httpServer.ts

@@ -0,0 +1,232 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import fs from 'fs';
+import path from 'path';
+import http from 'http';
+import net from 'net';
+
+import mime from 'mime';
+
+import { ManualPromise } from './manualPromise.js';
+
+
+export type ServerRouteHandler = (request: http.IncomingMessage, response: http.ServerResponse) => void;
+
+export type Transport = {
+  sendEvent?: (method: string, params: any) => void;
+  close?: () => void;
+  onconnect: () => void;
+  dispatch: (method: string, params: any) => Promise<any>;
+  onclose: () => void;
+};
+
+export class HttpServer {
+  private _server: http.Server;
+  private _urlPrefixPrecise: string = '';
+  private _urlPrefixHumanReadable: string = '';
+  private _port: number = 0;
+  private _routes: { prefix?: string, exact?: string, handler: ServerRouteHandler }[] = [];
+
+  constructor() {
+    this._server = http.createServer(this._onRequest.bind(this));
+    decorateServer(this._server);
+  }
+
+  server() {
+    return this._server;
+  }
+
+  routePrefix(prefix: string, handler: ServerRouteHandler) {
+    this._routes.push({ prefix, handler });
+  }
+
+  routePath(path: string, handler: ServerRouteHandler) {
+    this._routes.push({ exact: path, handler });
+  }
+
+  port(): number {
+    return this._port;
+  }
+
+  private async _tryStart(port: number | undefined, host: string) {
+    const errorPromise = new ManualPromise();
+    const errorListener = (error: Error) => errorPromise.reject(error);
+    this._server.on('error', errorListener);
+
+    try {
+      this._server.listen(port, host);
+      await Promise.race([
+        new Promise(cb => this._server!.once('listening', cb)),
+        errorPromise,
+      ]);
+    } finally {
+      this._server.removeListener('error', errorListener);
+    }
+  }
+
+  async start(options: { port?: number, preferredPort?: number, host?: string } = {}): Promise<void> {
+    const host = options.host || 'localhost';
+    if (options.preferredPort) {
+      try {
+        await this._tryStart(options.preferredPort, host);
+      } catch (e: any) {
+        if (!e || !e.message || !e.message.includes('EADDRINUSE'))
+          throw e;
+        await this._tryStart(undefined, host);
+      }
+    } else {
+      await this._tryStart(options.port, host);
+    }
+
+    const address = this._server.address();
+    if (typeof address === 'string') {
+      this._urlPrefixPrecise = address;
+      this._urlPrefixHumanReadable = address;
+    } else {
+      this._port = address!.port;
+      const resolvedHost = address!.family === 'IPv4' ? address!.address : `[${address!.address}]`;
+      this._urlPrefixPrecise = `http://${resolvedHost}:${address!.port}`;
+      this._urlPrefixHumanReadable = `http://${host}:${address!.port}`;
+    }
+  }
+
+  async stop() {
+    await new Promise(cb => this._server!.close(cb));
+  }
+
+  urlPrefix(purpose: 'human-readable' | 'precise'): string {
+    return purpose === 'human-readable' ? this._urlPrefixHumanReadable : this._urlPrefixPrecise;
+  }
+
+  serveFile(request: http.IncomingMessage, response: http.ServerResponse, absoluteFilePath: string, headers?: { [name: string]: string }): boolean {
+    try {
+      for (const [name, value] of Object.entries(headers || {}))
+        response.setHeader(name, value);
+      if (request.headers.range)
+        this._serveRangeFile(request, response, absoluteFilePath);
+      else
+        this._serveFile(response, absoluteFilePath);
+      return true;
+    } catch (e) {
+      return false;
+    }
+  }
+
+  _serveFile(response: http.ServerResponse, absoluteFilePath: string) {
+    const content = fs.readFileSync(absoluteFilePath);
+    response.statusCode = 200;
+    const contentType = mime.getType(path.extname(absoluteFilePath)) || 'application/octet-stream';
+    response.setHeader('Content-Type', contentType);
+    response.setHeader('Content-Length', content.byteLength);
+    response.end(content);
+  }
+
+  _serveRangeFile(request: http.IncomingMessage, response: http.ServerResponse, absoluteFilePath: string) {
+    const range = request.headers.range;
+    if (!range || !range.startsWith('bytes=') || range.includes(', ') || [...range].filter(char => char === '-').length !== 1) {
+      response.statusCode = 400;
+      return response.end('Bad request');
+    }
+
+    // Parse the range header: https://datatracker.ietf.org/doc/html/rfc7233#section-2.1
+    const [startStr, endStr] = range.replace(/bytes=/, '').split('-');
+
+    // Both start and end (when passing to fs.createReadStream) and the range header are inclusive and start counting at 0.
+    let start: number;
+    let end: number;
+    const size = fs.statSync(absoluteFilePath).size;
+    if (startStr !== '' && endStr === '') {
+      // No end specified: use the whole file
+      start = +startStr;
+      end = size - 1;
+    } else if (startStr === '' && endStr !== '') {
+      // No start specified: calculate start manually
+      start = size - +endStr;
+      end = size - 1;
+    } else {
+      start = +startStr;
+      end = +endStr;
+    }
+
+    // Handle unavailable range request
+    if (Number.isNaN(start) || Number.isNaN(end) || start >= size || end >= size || start > end) {
+      // Return the 416 Range Not Satisfiable: https://datatracker.ietf.org/doc/html/rfc7233#section-4.4
+      response.writeHead(416, {
+        'Content-Range': `bytes */${size}`
+      });
+      return response.end();
+    }
+
+    // Sending Partial Content: https://datatracker.ietf.org/doc/html/rfc7233#section-4.1
+    response.writeHead(206, {
+      'Content-Range': `bytes ${start}-${end}/${size}`,
+      'Accept-Ranges': 'bytes',
+      'Content-Length': end - start + 1,
+      'Content-Type': mime.getType(path.extname(absoluteFilePath))!,
+    });
+
+    const readable = fs.createReadStream(absoluteFilePath, { start, end });
+    readable.pipe(response);
+  }
+
+  private _onRequest(request: http.IncomingMessage, response: http.ServerResponse) {
+    if (request.method === 'OPTIONS') {
+      response.writeHead(200);
+      response.end();
+      return;
+    }
+
+    request.on('error', () => response.end());
+    try {
+      if (!request.url) {
+        response.end();
+        return;
+      }
+      const url = new URL('http://localhost' + request.url);
+      for (const route of this._routes) {
+        if (route.exact && url.pathname === route.exact) {
+          route.handler(request, response);
+          return;
+        }
+        if (route.prefix && url.pathname.startsWith(route.prefix)) {
+          route.handler(request, response);
+          return;
+        }
+      }
+      response.statusCode = 404;
+      response.end();
+    } catch (e) {
+      response.end();
+    }
+  }
+}
+
+function decorateServer(server: net.Server) {
+  const sockets = new Set<net.Socket>();
+  server.on('connection', socket => {
+    sockets.add(socket);
+    socket.once('close', () => sockets.delete(socket));
+  });
+
+  const close = server.close;
+  server.close = (callback?: (err?: Error) => void) => {
+    for (const socket of sockets)
+      socket.destroy();
+    sockets.clear();
+    return close.call(server, callback);
+  };
+}

src/index.ts

@@ -14,10 +14,33 @@
  * limitations under the License.
  */
 
-import { Connection, createConnection as createConnectionImpl } from './connection.js';
+import { createConnection as createConnectionImpl } from './connection.js';
+import type { Connection } from '../index.js';
+import { resolveConfig } from './config.js';
+import { contextFactory } from './browserContextFactory.js';
 
 import type { Config } from '../config.js';
+import type { BrowserContext } from 'playwright';
+import type { BrowserContextFactory } from './browserContextFactory.js';
 
-export async function createConnection(config: Config = {}): Promise<Connection> {
-  return createConnectionImpl(config);
+export async function createConnection(userConfig: Config = {}, contextGetter?: () => Promise<BrowserContext>): Promise<Connection> {
+  const config = await resolveConfig(userConfig);
+  const factory = contextGetter ? new SimpleBrowserContextFactory(contextGetter) : contextFactory(config.browser);
+  return createConnectionImpl(config, factory);
+}
+
+class SimpleBrowserContextFactory implements BrowserContextFactory {
+  private readonly _contextGetter: () => Promise<BrowserContext>;
+
+  constructor(contextGetter: () => Promise<BrowserContext>) {
+    this._contextGetter = contextGetter;
+  }
+
+  async createContext(): Promise<{ browserContext: BrowserContext, close: () => Promise<void> }> {
+    const browserContext = await this._contextGetter();
+    return {
+      browserContext,
+      close: () => browserContext.close()
+    };
+  }
 }

src/package.ts

@@ -0,0 +1,22 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import fs from 'node:fs';
+import url from 'node:url';
+import path from 'node:path';
+
+const __filename = url.fileURLToPath(import.meta.url);
+export const packageJSON = JSON.parse(fs.readFileSync(path.join(path.dirname(__filename), '..', 'package.json'), 'utf8'));

src/pageSnapshot.ts

@@ -15,6 +15,11 @@
  */
 
 import * as playwright from 'playwright';
+import { callOnPageNoTrace } from './tools/utils.js';
+
+type PageEx = playwright.Page & {
+  _snapshotForAI: () => Promise<string>;
+};
 
 export class PageSnapshot {
   private _page: playwright.Page;
@@ -35,16 +40,16 @@ export class PageSnapshot {
   }
 
   private async _build() {
-    const yamlDocument = await (this._page as any)._snapshotForAI();
+    const snapshot = await callOnPageNoTrace(this._page, page => (page as PageEx)._snapshotForAI());
     this._text = [
       `- Page Snapshot`,
       '```yaml',
-      yamlDocument.toString({ indentSeq: false }).trim(),
+      snapshot,
       '```',
     ].join('\n');
   }
 
-  refLocator(ref: string): playwright.Locator {
-    return this._page.locator(`aria-ref=${ref}`);
+  refLocator(params: { element: string, ref: string }): playwright.Locator {
+    return this._page.locator(`aria-ref=${params.ref}`).describe(params.element);
   }
 }

src/program.ts

@@ -14,13 +14,15 @@
  * limitations under the License.
  */
 
-import { program } from 'commander';
+import { Option, program } from 'commander';
+// @ts-ignore
+import { startTraceViewerServer } from 'playwright-core/lib/server';
 
-import { startHttpTransport, startStdioTransport } from './transport.js';
-import { resolveConfig } from './config.js';
-
-import type { Connection } from './connection.js';
-import { packageJSON } from './context.js';
+import { startHttpServer, startHttpTransport, startStdioTransport } from './transport.js';
+import { resolveCLIConfig } from './config.js';
+import { Server } from './server.js';
+import { packageJSON } from './package.js';
+import { startCDPRelayServer } from './cdpRelay.js';
 
 program
     .version('Version ' + packageJSON.version)
@@ -29,6 +31,7 @@ program
     .option('--blocked-origins <origins>', 'semicolon-separated list of origins to block the browser from requesting. Blocklist is evaluated before allowlist. If used without the allowlist, requests not matching the blocklist are still allowed.', semicolonSeparatedList)
     .option('--block-service-workers', 'block service workers')
     .option('--browser <browser>', 'browser or chrome channel to use, possible values: chrome, firefox, webkit, msedge.')
+    .option('--browser-agent <endpoint>', 'Use browser agent (experimental).')
     .option('--caps <caps>', 'comma-separated list of capabilities to enable, possible values: tabs, pdf, history, wait, files, install. Default is all.')
     .option('--cdp-endpoint <endpoint>', 'CDP endpoint to connect to.')
     .option('--config <path>', 'path to the configuration file.')
@@ -38,43 +41,48 @@ program
     .option('--host <host>', 'host to bind server to. Default is localhost. Use 0.0.0.0 to bind to all interfaces.')
     .option('--ignore-https-errors', 'ignore https errors')
     .option('--isolated', 'keep the browser profile in memory, do not save it to disk.')
-    .option('--no-image-responses', 'do not send image responses to the client.')
+    .option('--image-responses <mode>', 'whether to send image responses to the client. Can be "allow", "omit", or "auto". Defaults to "auto", which sends images if the client can display them.')
     .option('--no-sandbox', 'disable the sandbox for all process types that are normally sandboxed.')
     .option('--output-dir <path>', 'path to the directory for output files.')
     .option('--port <port>', 'port to listen on for SSE transport.')
     .option('--proxy-bypass <bypass>', 'comma-separated domains to bypass proxy, for example ".com,chromium.org,.domain.com"')
     .option('--proxy-server <proxy>', 'specify proxy server, for example "http://myproxy:3128" or "socks5://myproxy:8080"')
+    .option('--save-trace', 'Whether to save the Playwright Trace of the session into the output directory.')
     .option('--storage-state <path>', 'path to the storage state file for isolated sessions.')
     .option('--user-agent <ua string>', 'specify user agent string')
     .option('--user-data-dir <path>', 'path to the user data directory. If not specified, a temporary directory will be created.')
     .option('--viewport-size <size>', 'specify browser viewport size in pixels, for example "1280, 720"')
     .option('--vision', 'Run server that uses screenshots (Aria snapshots are used by default)')
+    .addOption(new Option('--extension', 'Allow connecting to a running browser instance (Edge/Chrome only). Requires the \'Playwright MCP\' browser extension to be installed.').hideHelp())
     .action(async options => {
-      const config = await resolveConfig(options);
-      const connectionList: Connection[] = [];
-      setupExitWatchdog(connectionList);
+      const config = await resolveCLIConfig(options);
+      const httpServer = config.server.port !== undefined ? await startHttpServer(config.server) : undefined;
+      if (config.extension) {
+        if (!httpServer)
+          throw new Error('--port parameter is required for extension mode');
+        // Point CDP endpoint to the relay server.
+        config.browser.cdpEndpoint = await startCDPRelayServer(httpServer);
+      }
 
-      if (options.port)
-        startHttpTransport(config, +options.port, options.host, connectionList);
+      const server = new Server(config);
+      server.setupExitWatchdog();
+
+      if (httpServer)
+        await startHttpTransport(httpServer, server);
       else
-        await startStdioTransport(config, connectionList);
+        await startStdioTransport(server);
+
+      if (config.saveTrace) {
+        const server = await startTraceViewerServer();
+        const urlPrefix = server.urlPrefix('human-readable');
+        const url = urlPrefix + '/trace/index.html?trace=' + config.browser.launchOptions.tracesDir + '/trace.json';
+        // eslint-disable-next-line no-console
+        console.error('\nTrace viewer listening on ' + url);
+      }
     });
 
-function setupExitWatchdog(connectionList: Connection[]) {
-  const handleExit = async () => {
-    setTimeout(() => process.exit(0), 15000);
-    for (const connection of connectionList)
-      await connection.close();
-    process.exit(0);
-  };
-
-  process.stdin.on('close', handleExit);
-  process.on('SIGINT', handleExit);
-  process.on('SIGTERM', handleExit);
-}
-
 function semicolonSeparatedList(value: string): string[] {
   return value.split(';').map(v => v.trim());
 }
 
-program.parse(process.argv);
+void program.parseAsync(process.argv);

src/server.ts

@@ -0,0 +1,59 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { createConnection } from './connection.js';
+import { contextFactory } from './browserContextFactory.js';
+
+import type { FullConfig } from './config.js';
+import type { Connection } from './connection.js';
+import type { Transport } from '@modelcontextprotocol/sdk/shared/transport.js';
+import type { BrowserContextFactory } from './browserContextFactory.js';
+
+export class Server {
+  readonly config: FullConfig;
+  private _connectionList: Connection[] = [];
+  private _browserConfig: FullConfig['browser'];
+  private _contextFactory: BrowserContextFactory;
+
+  constructor(config: FullConfig) {
+    this.config = config;
+    this._browserConfig = config.browser;
+    this._contextFactory = contextFactory(this._browserConfig);
+  }
+
+  async createConnection(transport: Transport): Promise<Connection> {
+    const connection = createConnection(this.config, this._contextFactory);
+    this._connectionList.push(connection);
+    await connection.server.connect(transport);
+    return connection;
+  }
+
+  setupExitWatchdog() {
+    let isExiting = false;
+    const handleExit = async () => {
+      if (isExiting)
+        return;
+      isExiting = true;
+      setTimeout(() => process.exit(0), 15000);
+      await Promise.all(this._connectionList.map(connection => connection.close()));
+      process.exit(0);
+    };
+
+    process.stdin.on('close', handleExit);
+    process.on('SIGINT', handleExit);
+    process.on('SIGTERM', handleExit);
+  }
+}

src/tab.ts

@@ -19,6 +19,7 @@ import * as playwright from 'playwright';
 import { PageSnapshot } from './pageSnapshot.js';
 
 import type { Context } from './context.js';
+import { callOnPageNoTrace } from './tools/utils.js';
 
 export class Tab {
   readonly context: Context;
@@ -61,10 +62,18 @@ export class Tab {
     this._onPageClose(this);
   }
 
+  async title(): Promise<string> {
+    return await callOnPageNoTrace(this.page, page => page.title());
+  }
+
+  async waitForLoadState(state: 'load', options?: { timeout?: number }): Promise<void> {
+    await callOnPageNoTrace(this.page, page => page.waitForLoadState(state, options).catch(() => {}));
+  }
+
   async navigate(url: string) {
     this._clearCollectedArtifacts();
 
-    const downloadEvent = this.page.waitForEvent('download').catch(() => {});
+    const downloadEvent = callOnPageNoTrace(this.page, page => page.waitForEvent('download').catch(() => {}));
     try {
       await this.page.goto(url, { waitUntil: 'domcontentloaded' });
     } catch (_e: unknown) {
@@ -74,18 +83,17 @@ export class Tab {
         || e.message.includes('Download is starting'); // firefox + webkit
       if (!mightBeDownload)
         throw e;
-
       // on chromium, the download event is fired *after* page.goto rejects, so we wait a lil bit
       const download = await Promise.race([
         downloadEvent,
-        new Promise(resolve => setTimeout(resolve, 500)),
+        new Promise(resolve => setTimeout(resolve, 1000)),
       ]);
       if (!download)
         throw e;
     }
 
     // Cap load event to 5 seconds, the page is operational at this point.
-    await this.page.waitForLoadState('load', { timeout: 5000 }).catch(() => {});
+    await this.waitForLoadState('load', { timeout: 5000 });
   }
 
   hasSnapshot(): boolean {

src/tools/common.ts

@@ -34,6 +34,12 @@ const close = defineTool({
       code: [`await page.close()`],
       captureSnapshot: false,
       waitForNetwork: false,
+      resultOverride: {
+        content: [{
+          type: 'text',
+          text: 'Browser closed successfully.',
+        }],
+      },
     };
   },
 });

src/tools/screenshot.ts

@@ -57,14 +57,14 @@ const screenshot = defineTool({
       `// Screenshot ${isElementScreenshot ? params.element : 'viewport'} and save it as ${fileName}`,
     ];
 
-    const locator = params.ref ? snapshot.refLocator(params.ref) : null;
+    const locator = params.ref ? snapshot.refLocator({ element: params.element || '', ref: params.ref }) : null;
 
     if (locator)
       code.push(`await page.${await generateLocator(locator)}.screenshot(${javascript.formatObject(options)});`);
     else
       code.push(`await page.screenshot(${javascript.formatObject(options)});`);
 
-    const includeBase64 = !context.config.noImageResponses;
+    const includeBase64 = context.clientSupportsImages();
     const action = async () => {
       const screenshot = locator ? await locator.screenshot(options) : await tab.page.screenshot(options);
       return {

src/tools/snapshot.ts

@@ -58,7 +58,7 @@ const click = defineTool({
 
   handle: async (context, params) => {
     const tab = context.currentTabOrDie();
-    const locator = tab.snapshotOrDie().refLocator(params.ref);
+    const locator = tab.snapshotOrDie().refLocator(params);
 
     const code = [
       `// Click ${params.element}`,
@@ -91,8 +91,8 @@ const drag = defineTool({
 
   handle: async (context, params) => {
     const snapshot = context.currentTabOrDie().snapshotOrDie();
-    const startLocator = snapshot.refLocator(params.startRef);
-    const endLocator = snapshot.refLocator(params.endRef);
+    const startLocator = snapshot.refLocator({ ref: params.startRef, element: params.startElement });
+    const endLocator = snapshot.refLocator({ ref: params.endRef, element: params.endElement });
 
     const code = [
       `// Drag ${params.startElement} to ${params.endElement}`,
@@ -120,7 +120,7 @@ const hover = defineTool({
 
   handle: async (context, params) => {
     const snapshot = context.currentTabOrDie().snapshotOrDie();
-    const locator = snapshot.refLocator(params.ref);
+    const locator = snapshot.refLocator(params);
 
     const code = [
       `// Hover over ${params.element}`,
@@ -154,7 +154,7 @@ const type = defineTool({
 
   handle: async (context, params) => {
     const snapshot = context.currentTabOrDie().snapshotOrDie();
-    const locator = snapshot.refLocator(params.ref);
+    const locator = snapshot.refLocator(params);
 
     const code: string[] = [];
     const steps: (() => Promise<void>)[] = [];
@@ -200,7 +200,7 @@ const selectOption = defineTool({
 
   handle: async (context, params) => {
     const snapshot = context.currentTabOrDie().snapshotOrDie();
-    const locator = snapshot.refLocator(params.ref);
+    const locator = snapshot.refLocator(params);
 
     const code = [
       `// Select options [${params.values.join(', ')}] in ${params.element}`,

src/tools/utils.ts

@@ -16,8 +16,9 @@
 
 import type * as playwright from 'playwright';
 import type { Context } from '../context.js';
+import type { Tab } from '../tab.js';
 
-export async function waitForCompletion<R>(context: Context, page: playwright.Page, callback: () => Promise<R>): Promise<R> {
+export async function waitForCompletion<R>(context: Context, tab: Tab, callback: () => Promise<R>): Promise<R> {
   const requests = new Set<playwright.Request>();
   let frameNavigated = false;
   let waitCallback: () => void = () => {};
@@ -36,9 +37,7 @@ export async function waitForCompletion<R>(context: Context, page: playwright.Pa
     frameNavigated = true;
     dispose();
     clearTimeout(timeout);
-    void frame.waitForLoadState('load').then(() => {
-      waitCallback();
-    });
+    void tab.waitForLoadState('load').then(waitCallback);
   };
 
   const onTimeout = () => {
@@ -46,15 +45,15 @@ export async function waitForCompletion<R>(context: Context, page: playwright.Pa
     waitCallback();
   };
 
-  page.on('request', requestListener);
-  page.on('requestfinished', requestFinishedListener);
-  page.on('framenavigated', frameNavigateListener);
+  tab.page.on('request', requestListener);
+  tab.page.on('requestfinished', requestFinishedListener);
+  tab.page.on('framenavigated', frameNavigateListener);
   const timeout = setTimeout(onTimeout, 10000);
 
   const dispose = () => {
-    page.off('request', requestListener);
-    page.off('requestfinished', requestFinishedListener);
-    page.off('framenavigated', frameNavigateListener);
+    tab.page.off('request', requestListener);
+    tab.page.off('requestfinished', requestFinishedListener);
+    tab.page.off('framenavigated', frameNavigateListener);
     clearTimeout(timeout);
   };
 
@@ -79,5 +78,15 @@ export function sanitizeForFilePath(s: string) {
 }
 
 export async function generateLocator(locator: playwright.Locator): Promise<string> {
-  return (locator as any)._generateLocatorString();
+  try {
+    return await (locator as any)._generateLocatorString();
+  } catch (e) {
+    if (e instanceof Error && /locator._generateLocatorString: Timeout .* exceeded/.test(e.message))
+      throw new Error('Ref not found, likely because element was removed. Use browser_snapshot to see what elements are currently on the page.');
+    throw e;
+  }
+}
+
+export async function callOnPageNoTrace<T>(page: playwright.Page, callback: (page: playwright.Page) => Promise<T>): Promise<T> {
+  return await (page as any)._wrapApiCall(() => callback(page), { internal: true });
 }

src/transport.ts

@@ -18,22 +18,21 @@ import http from 'node:http';
 import assert from 'node:assert';
 import crypto from 'node:crypto';
 
+import debug from 'debug';
 import { SSEServerTransport } from '@modelcontextprotocol/sdk/server/sse.js';
 import { StreamableHTTPServerTransport } from '@modelcontextprotocol/sdk/server/streamableHttp.js';
 import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
 
-import { createConnection } from './connection.js';
+import type { AddressInfo } from 'node:net';
+import type { Server } from './server.js';
 
-import type { Config } from '../config.js';
-import type { Connection } from './connection.js';
-
-export async function startStdioTransport(config: Config, connectionList: Connection[]) {
-  const connection = await createConnection(config);
-  await connection.connect(new StdioServerTransport());
-  connectionList.push(connection);
+export async function startStdioTransport(server: Server) {
+  await server.createConnection(new StdioServerTransport());
 }
 
-async function handleSSE(config: Config, req: http.IncomingMessage, res: http.ServerResponse, url: URL, sessions: Map<string, SSEServerTransport>, connectionList: Connection[]) {
+const testDebug = debug('pw:mcp:test');
+
+async function handleSSE(server: Server, req: http.IncomingMessage, res: http.ServerResponse, url: URL, sessions: Map<string, SSEServerTransport>) {
   if (req.method === 'POST') {
     const sessionId = url.searchParams.get('sessionId');
     if (!sessionId) {
@@ -51,15 +50,13 @@ async function handleSSE(config: Config, req: http.IncomingMessage, res: http.Se
   } else if (req.method === 'GET') {
     const transport = new SSEServerTransport('/sse', res);
     sessions.set(transport.sessionId, transport);
-    const connection = await createConnection(config);
-    await connection.connect(transport);
-    connectionList.push(connection);
+    testDebug(`create SSE session: ${transport.sessionId}`);
+    const connection = await server.createConnection(transport);
     res.on('close', () => {
+      testDebug(`delete SSE session: ${transport.sessionId}`);
       sessions.delete(transport.sessionId);
-      connection.close().catch(e => {
-        // eslint-disable-next-line no-console
-        console.error(e);
-      });
+      // eslint-disable-next-line no-console
+      void connection.close().catch(e => console.error(e));
     });
     return;
   }
@@ -68,7 +65,7 @@ async function handleSSE(config: Config, req: http.IncomingMessage, res: http.Se
   res.end('Method not allowed');
 }
 
-async function handleStreamable(config: Config, req: http.IncomingMessage, res: http.ServerResponse, sessions: Map<string, StreamableHTTPServerTransport>, connectionList: Connection[]) {
+async function handleStreamable(server: Server, req: http.IncomingMessage, res: http.ServerResponse, sessions: Map<string, StreamableHTTPServerTransport>) {
   const sessionId = req.headers['mcp-session-id'] as string | undefined;
   if (sessionId) {
     const transport = sessions.get(sessionId);
@@ -91,12 +88,8 @@ async function handleStreamable(config: Config, req: http.IncomingMessage, res:
       if (transport.sessionId)
         sessions.delete(transport.sessionId);
     };
-    const connection = await createConnection(config);
-    connectionList.push(connection);
-    await Promise.all([
-      connection.connect(transport),
-      transport.handleRequest(req, res),
-    ]);
+    await server.createConnection(transport);
+    await transport.handleRequest(req, res);
     return;
   }
 
@@ -104,42 +97,53 @@ async function handleStreamable(config: Config, req: http.IncomingMessage, res:
   res.end('Invalid request');
 }
 
-export function startHttpTransport(config: Config, port: number, hostname: string | undefined, connectionList: Connection[]) {
+export async function startHttpServer(config: { host?: string, port?: number }): Promise<http.Server> {
+  const { host, port } = config;
+  const httpServer = http.createServer();
+  await new Promise<void>((resolve, reject) => {
+    httpServer.on('error', reject);
+    httpServer.listen(port, host, () => {
+      resolve();
+      httpServer.removeListener('error', reject);
+    });
+  });
+  return httpServer;
+}
+
+export function startHttpTransport(httpServer: http.Server, mcpServer: Server) {
   const sseSessions = new Map<string, SSEServerTransport>();
   const streamableSessions = new Map<string, StreamableHTTPServerTransport>();
-  const httpServer = http.createServer(async (req, res) => {
+  httpServer.on('request', async (req, res) => {
     const url = new URL(`http://localhost${req.url}`);
     if (url.pathname.startsWith('/mcp'))
-      await handleStreamable(config, req, res, streamableSessions, connectionList);
+      await handleStreamable(mcpServer, req, res, streamableSessions);
     else
-      await handleSSE(config, req, res, url, sseSessions, connectionList);
+      await handleSSE(mcpServer, req, res, url, sseSessions);
   });
-  httpServer.listen(port, hostname, () => {
-    const address = httpServer.address();
-    assert(address, 'Could not bind server socket');
-    let url: string;
-    if (typeof address === 'string') {
-      url = address;
-    } else {
-      const resolvedPort = address.port;
-      let resolvedHost = address.family === 'IPv4' ? address.address : `[${address.address}]`;
-      if (resolvedHost === '0.0.0.0' || resolvedHost === '[::]')
-        resolvedHost = 'localhost';
-      url = `http://${resolvedHost}:${resolvedPort}`;
-    }
-    const message = [
-      `Listening on ${url}`,
-      'Put this in your client config:',
-      JSON.stringify({
-        'mcpServers': {
-          'playwright': {
-            'url': `${url}/sse`
-          }
+  const url = httpAddressToString(httpServer.address());
+  const message = [
+    `Listening on ${url}`,
+    'Put this in your client config:',
+    JSON.stringify({
+      'mcpServers': {
+        'playwright': {
+          'url': `${url}/sse`
         }
-      }, undefined, 2),
-      'If your client supports streamable HTTP, you can use the /mcp endpoint instead.',
-    ].join('\n');
+      }
+    }, undefined, 2),
+    'If your client supports streamable HTTP, you can use the /mcp endpoint instead.',
+  ].join('\n');
     // eslint-disable-next-line no-console
-    console.log(message);
-  });
+  console.error(message);
+}
+
+export function httpAddressToString(address: string | AddressInfo | null): string {
+  assert(address, 'Could not bind server socket');
+  if (typeof address === 'string')
+    return address;
+  const resolvedPort = address.port;
+  let resolvedHost = address.family === 'IPv4' ? address.address : `[${address.address}]`;
+  if (resolvedHost === '0.0.0.0' || resolvedHost === '[::]')
+    resolvedHost = 'localhost';
+  return `http://${resolvedHost}:${resolvedPort}`;
 }

tests/browser-server.spec.ts

@@ -0,0 +1,77 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import path from 'path';
+import url from 'node:url';
+
+import { spawn } from 'child_process';
+import { test as baseTest, expect } from './fixtures.js';
+
+import type { ChildProcess } from 'child_process';
+
+const __filename = url.fileURLToPath(import.meta.url);
+
+const test = baseTest.extend<{ agentEndpoint: (options?: { args?: string[] }) => Promise<{ url: URL, stdout: () => string }> }>({
+  agentEndpoint: async ({}, use) => {
+    let cp: ChildProcess | undefined;
+    await use(async (options?: { args?: string[] }) => {
+      if (cp)
+        throw new Error('Process already running');
+
+      cp = spawn('node', [
+        path.join(path.dirname(__filename), '../lib/browserServer.js'),
+        ...(options?.args || []),
+      ], {
+        stdio: 'pipe',
+        env: {
+          ...process.env,
+          DEBUG: 'pw:mcp:test',
+          DEBUG_COLORS: '0',
+          DEBUG_HIDE_DATE: '1',
+        },
+      });
+      let stdout = '';
+      const url = await new Promise<string>(resolve => cp!.stdout?.on('data', data => {
+        stdout += data.toString();
+        const match = stdout.match(/Listening on (http:\/\/.*)/);
+        if (match)
+          resolve(match[1]);
+      }));
+
+      return { url: new URL(url), stdout: () => stdout };
+    });
+    cp?.kill('SIGTERM');
+  },
+});
+
+test.skip(({ mcpBrowser }) => mcpBrowser !== 'chrome', 'Agent is CDP-only for now');
+
+test('browser lifecycle', async ({ agentEndpoint, startClient, server }) => {
+  const { url: agentUrl } = await agentEndpoint();
+  const { client: client1 } = await startClient({ args: ['--browser-agent', agentUrl.toString()] });
+  expect(await client1.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  })).toContainTextContent('Hello, world!');
+
+  const { client: client2 } = await startClient({ args: ['--browser-agent', agentUrl.toString()] });
+  expect(await client2.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  })).toContainTextContent('Hello, world!');
+
+  await client1.close();
+  await client2.close();
+});

tests/capabilities.spec.ts

@@ -77,7 +77,7 @@ test('test vision tool list', async ({ visionClient }) => {
 });
 
 test('test capabilities', async ({ startClient }) => {
-  const client = await startClient({
+  const { client } = await startClient({
     args: ['--caps="core"'],
   });
   const { tools } = await client.listTools();

tests/cdp.spec.ts

@@ -14,18 +14,28 @@
  * limitations under the License.
  */
 
+import url from 'node:url';
+import path from 'node:path';
+import { spawnSync } from 'node:child_process';
 import { test, expect } from './fixtures.js';
 
-test('cdp server', async ({ cdpEndpoint, startClient, server }) => {
-  const client = await startClient({ args: [`--cdp-endpoint=${await cdpEndpoint()}`] });
+test.skip(({ mcpMode }) => mcpMode === 'extension', 'Connecting to CDP server is not supported in combination with --extension');
+
+test('cdp server', async ({ cdpServer, startClient, server }) => {
+  await cdpServer.start();
+  const { client } = await startClient({ args: [`--cdp-endpoint=${cdpServer.endpoint}`] });
   expect(await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.HELLO_WORLD },
   })).toContainTextContent(`- generic [ref=e1]: Hello, world!`);
 });
 
-test('cdp server reuse tab', async ({ cdpEndpoint, startClient }) => {
-  const client = await startClient({ args: [`--cdp-endpoint=${await cdpEndpoint()}`] });
+test('cdp server reuse tab', async ({ cdpServer, startClient, server }) => {
+  const browserContext = await cdpServer.start();
+  const { client } = await startClient({ args: [`--cdp-endpoint=${cdpServer.endpoint}`] });
+
+  const [page] = browserContext.pages();
+  await page.goto(server.HELLO_WORLD);
 
   expect(await client.callTool({
     name: 'browser_click',
@@ -33,7 +43,7 @@ test('cdp server reuse tab', async ({ cdpEndpoint, startClient }) => {
       element: 'Hello, world!',
       ref: 'f0',
     },
-  })).toHaveTextContent(`Error: No current snapshot available. Capture a snapshot of navigate to a new location first.`);
+  })).toHaveTextContent(`Error: No current snapshot available. Capture a snapshot or navigate to a new location first.`);
 
   expect(await client.callTool({
     name: 'browser_snapshot',
@@ -43,18 +53,17 @@ test('cdp server reuse tab', async ({ cdpEndpoint, startClient }) => {
 // <internal code to capture accessibility snapshot>
 \`\`\`
 
-- Page URL: data:text/html,hello world
-- Page Title: 
+- Page URL: ${server.HELLO_WORLD}
+- Page Title: Title
 - Page Snapshot
 \`\`\`yaml
-- generic [ref=e1]: hello world
+- generic [ref=e1]: Hello, world!
 \`\`\`
 `);
 });
 
-test('should throw connection error and allow re-connecting', async ({ cdpEndpoint, startClient, server }) => {
-  const port = 3200 + test.info().parallelIndex;
-  const client = await startClient({ args: [`--cdp-endpoint=http://localhost:${port}`] });
+test('should throw connection error and allow re-connecting', async ({ cdpServer, startClient, server }) => {
+  const { client } = await startClient({ args: [`--cdp-endpoint=${cdpServer.endpoint}`] });
 
   server.setContent('/', `
     <title>Title</title>
@@ -65,9 +74,21 @@ test('should throw connection error and allow re-connecting', async ({ cdpEndpoi
     name: 'browser_navigate',
     arguments: { url: server.PREFIX },
   })).toContainTextContent(`Error: browserType.connectOverCDP: connect ECONNREFUSED`);
-  await cdpEndpoint(port);
+  await cdpServer.start();
   expect(await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.PREFIX },
   })).toContainTextContent(`- generic [ref=e1]: Hello, world!`);
 });
+
+// NOTE: Can be removed when we drop Node.js 18 support and changed to import.meta.filename.
+const __filename = url.fileURLToPath(import.meta.url);
+
+test('does not support --device', async () => {
+  const result = spawnSync('node', [
+    path.join(__filename, '../../cli.js'), '--device=Pixel 5', '--cdp-endpoint=http://localhost:1234',
+  ]);
+  expect(result.error).toBeUndefined();
+  expect(result.status).toBe(1);
+  expect(result.stderr.toString()).toContain('Device emulation is not supported with cdpEndpoint.');
+});

tests/config.spec.ts

@@ -19,7 +19,8 @@ import fs from 'node:fs';
 import { Config } from '../config.js';
 import { test, expect } from './fixtures.js';
 
-test('config user data dir', async ({ startClient, localOutputPath, server }) => {
+test('config user data dir', async ({ startClient, server, mcpMode }, testInfo) => {
+  test.skip(mcpMode === 'extension', 'Connecting to CDP server does not use user data dir');
   server.setContent('/', `
     <title>Title</title>
     <body>Hello, world!</body>
@@ -27,13 +28,13 @@ test('config user data dir', async ({ startClient, localOutputPath, server }) =>
 
   const config: Config = {
     browser: {
-      userDataDir: localOutputPath('user-data-dir'),
+      userDataDir: testInfo.outputPath('user-data-dir'),
     },
   };
-  const configPath = localOutputPath('config.json');
+  const configPath = testInfo.outputPath('config.json');
   await fs.promises.writeFile(configPath, JSON.stringify(config, null, 2));
 
-  const client = await startClient({ args: ['--config', configPath] });
+  const { client } = await startClient({ args: ['--config', configPath] });
   expect(await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.PREFIX },
@@ -42,3 +43,23 @@ test('config user data dir', async ({ startClient, localOutputPath, server }) =>
   const files = await fs.promises.readdir(config.browser!.userDataDir!);
   expect(files.length).toBeGreaterThan(0);
 });
+
+test.describe(() => {
+  test.use({ mcpBrowser: '' });
+  test('browserName', { annotation: { type: 'issue', description: 'https://github.com/microsoft/playwright-mcp/issues/458' } }, async ({ startClient, mcpMode }, testInfo) => {
+    test.skip(mcpMode === 'extension', 'Extension mode only supports Chromium');
+    const config: Config = {
+      browser: {
+        browserName: 'firefox',
+      },
+    };
+    const configPath = testInfo.outputPath('config.json');
+    await fs.promises.writeFile(configPath, JSON.stringify(config, null, 2));
+
+    const { client } = await startClient({ args: ['--config', configPath] });
+    expect(await client.callTool({
+      name: 'browser_navigate',
+      arguments: { url: 'data:text/html,<script>document.title = navigator.userAgent</script>' },
+    })).toContainTextContent(`Firefox`);
+  });
+});

tests/core.spec.ts

@@ -237,3 +237,41 @@ await page.setViewportSize({ width: 390, height: 780 });
 \`\`\``);
   await expect.poll(() => client.callTool({ name: 'browser_snapshot' })).toContainTextContent('Window size: 390x780');
 });
+
+test('old locator error message', async ({ client, server }) => {
+  server.setContent('/', `
+    <button>Button 1</button>
+    <button>Button 2</button>
+    <script>
+      document.querySelector('button').addEventListener('click', () => {
+        document.querySelectorAll('button')[1].remove();
+      });
+    </script>
+  `, 'text/html');
+
+  expect(await client.callTool({
+    name: 'browser_navigate',
+    arguments: {
+      url: server.PREFIX,
+    },
+  })).toContainTextContent(`
+  - button "Button 1" [ref=e2]
+  - button "Button 2" [ref=e3]
+  `.trim());
+
+  await client.callTool({
+    name: 'browser_click',
+    arguments: {
+      element: 'Button 1',
+      ref: 'e2',
+    },
+  });
+
+  expect(await client.callTool({
+    name: 'browser_click',
+    arguments: {
+      element: 'Button 2',
+      ref: 'e3',
+    },
+  })).toContainTextContent('Ref not found');
+});

tests/device.spec.ts

@@ -16,8 +16,9 @@
 
 import { test, expect } from './fixtures.js';
 
-test('--device should work', async ({ startClient, server }) => {
-  const client = await startClient({
+test('--device should work', async ({ startClient, server, mcpMode }) => {
+  test.skip(mcpMode === 'extension', 'Viewport is not supported when connecting via CDP. There we re-use the browser viewport.');
+  const { client } = await startClient({
     args: ['--device', 'iPhone 15'],
   });
 

tests/extension.spec.ts

@@ -0,0 +1,43 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import url from 'url';
+import path from 'path';
+import { spawnSync } from 'child_process';
+
+import { test, expect } from './fixtures.js';
+
+import { createConnection } from '@playwright/mcp';
+
+test.skip(({ mcpMode }) => mcpMode !== 'extension');
+
+test('does not allow --cdp-endpoint', async ({  startClient }) => {
+  await expect(createConnection({
+    browser: { browserName: 'firefox' },
+    ...({ extension: true })
+  })).rejects.toThrow(/Extension mode is only supported for Chromium browsers/);
+});
+
+// NOTE: Can be removed when we drop Node.js 18 support and changed to import.meta.filename.
+const __filename = url.fileURLToPath(import.meta.url);
+
+test('does not support --device', async () => {
+  const result = spawnSync('node', [
+    path.join(__filename, '../../cli.js'), '--device=Pixel 5', '--extension',
+  ]);
+  expect(result.error).toBeUndefined();
+  expect(result.status).toBe(1);
+  expect(result.stderr.toString()).toContain('Device emulation is not supported with extension mode.');
+});

tests/files.spec.ts

@@ -16,9 +16,8 @@
 
 import { test, expect } from './fixtures.js';
 import fs from 'fs/promises';
-import path from 'path';
 
-test('browser_file_upload', async ({ client, localOutputPath, server }) => {
+test('browser_file_upload', async ({ client, server }, testInfo) => {
   server.setContent('/', `
     <input type="file" />
     <button>Button</button>
@@ -54,7 +53,7 @@ The tool "browser_file_upload" can only be used when there is related modal stat
   })).toContainTextContent(`### Modal state
 - [File chooser]: can be handled by the "browser_file_upload" tool`);
 
-  const filePath = localOutputPath('test.txt');
+  const filePath = testInfo.outputPath('test.txt');
   await fs.writeFile(filePath, 'Hello, world!');
 
   {
@@ -101,10 +100,10 @@ The tool "browser_file_upload" can only be used when there is related modal stat
   }
 });
 
-test('clicking on download link emits download', async ({ startClient, localOutputPath, server }) => {
-  const outputDir = localOutputPath('output');
-  const client = await startClient({
-    config: { outputDir },
+test('clicking on download link emits download', async ({ startClient, server, mcpMode }, testInfo) => {
+  test.fixme(mcpMode === 'extension', 'Downloads are on the Browser CDP domain and not supported with --extension');
+  const { client } = await startClient({
+    config: { outputDir: testInfo.outputPath('output') },
   });
 
   server.setContent('/', `<a href="/download" download="test.txt">Download</a>`, 'text/html');
@@ -123,10 +122,15 @@ test('clicking on download link emits download', async ({ startClient, localOutp
   });
   await expect.poll(() => client.callTool({ name: 'browser_snapshot' })).toContainTextContent(`
 ### Downloads
-- Downloaded file test.txt to ${path.join(outputDir, 'test.txt')}`);
+- Downloaded file test.txt to ${testInfo.outputPath('output', 'test.txt')}`);
 });
 
-test('navigating to download link emits download', async ({ client, server, mcpBrowser }) => {
+test('navigating to download link emits download', async ({ startClient, server, mcpBrowser, mcpMode }, testInfo) => {
+  test.fixme(mcpMode === 'extension', 'Downloads are on the Browser CDP domain and not supported with --extension');
+  const { client } = await startClient({
+    config: { outputDir: testInfo.outputPath('output') },
+  });
+
   test.skip(mcpBrowser === 'webkit' && process.platform === 'linux', 'https://github.com/microsoft/playwright/blob/8e08fdb52c27bb75de9bf87627bf740fadab2122/tests/library/download.spec.ts#L436');
   server.route('/download', (req, res) => {
     res.writeHead(200, {

tests/fixtures.ts

@@ -17,31 +17,42 @@
 import fs from 'fs';
 import url from 'url';
 import path from 'path';
+import net from 'net';
 import { chromium } from 'playwright';
+import { fork } from 'child_process';
 
 import { test as baseTest, expect as baseExpect } from '@playwright/test';
 import { StdioClientTransport } from '@modelcontextprotocol/sdk/client/stdio.js';
+import { SSEClientTransport } from '@modelcontextprotocol/sdk/client/sse.js';
 import { Client } from '@modelcontextprotocol/sdk/client/index.js';
-import { ChildProcessWithoutNullStreams, spawn } from 'child_process';
 import { TestServer } from './testserver/index.ts';
+import { ManualPromise } from '../src/manualPromise.js';
 
 import type { Config } from '../config';
+import type { BrowserContext } from 'playwright';
+import type { Transport } from '@modelcontextprotocol/sdk/shared/transport.js';
+import type { Stream } from 'stream';
 
 export type TestOptions = {
   mcpBrowser: string | undefined;
-  mcpMode: 'docker' | undefined;
+  mcpMode: 'docker' | 'extension' | undefined;
+};
+
+type CDPServer = {
+  endpoint: string;
+  start: () => Promise<BrowserContext>;
 };
 
 type TestFixtures = {
   client: Client;
   visionClient: Client;
-  startClient: (options?: { clientName?: string, args?: string[], config?: Config }) => Promise<Client>;
+  startClient: (options?: { clientName?: string, args?: string[], config?: Config }) => Promise<{ client: Client, stderr: () => string }>;
   wsEndpoint: string;
-  cdpEndpoint: (port?: number) => Promise<string>;
+  cdpServer: CDPServer;
   server: TestServer;
   httpsServer: TestServer;
   mcpHeadless: boolean;
-  localOutputPath: (filePath: string) => string;
+  startMcpExtension: (relayServerURL: string) => Promise<void>;
 };
 
 type WorkerFixtures = {
@@ -51,20 +62,24 @@ type WorkerFixtures = {
 export const test = baseTest.extend<TestFixtures & TestOptions, WorkerFixtures>({
 
   client: async ({ startClient }, use) => {
-    await use(await startClient());
+    const { client } = await startClient();
+    await use(client);
   },
 
   visionClient: async ({ startClient }, use) => {
-    await use(await startClient({ args: ['--vision'] }));
+    const { client } = await startClient({ args: ['--vision'] });
+    await use(client);
   },
 
-  startClient: async ({ mcpHeadless, mcpBrowser, mcpMode }, use, testInfo) => {
-    const userDataDir = testInfo.outputPath('user-data-dir');
+  startClient: async ({ mcpHeadless, mcpBrowser, mcpMode, startMcpExtension }, use, testInfo) => {
+    const userDataDir = mcpMode !== 'docker' ? testInfo.outputPath('user-data-dir') : undefined;
     const configDir = path.dirname(test.info().config.configFile!);
     let client: Client | undefined;
 
     await use(async options => {
-      const args = ['--user-data-dir', path.relative(configDir, userDataDir)];
+      const args: string[] = [];
+      if (userDataDir)
+        args.push('--user-data-dir', userDataDir);
       if (process.env.CI && process.platform === 'linux')
         args.push('--no-sandbox');
       if (mcpHeadless)
@@ -80,10 +95,18 @@ export const test = baseTest.extend<TestFixtures & TestOptions, WorkerFixtures>(
       }
 
       client = new Client({ name: options?.clientName ?? 'test', version: '1.0.0' });
-      const transport = createTransport(args, mcpMode);
+      const { transport, stderr, relayServerURL } = await createTransport(args, mcpMode);
+      let stderrBuffer = '';
+      stderr?.on('data', data => {
+        if (process.env.PWMCP_DEBUG)
+          process.stderr.write(data);
+        stderrBuffer += data.toString();
+      });
       await client.connect(transport);
+      if (mcpMode === 'extension')
+        await startMcpExtension(relayServerURL!);
       await client.ping();
-      return client;
+      return { client, stderr: () => stderrBuffer };
     });
 
     await client?.close();
@@ -95,39 +118,25 @@ export const test = baseTest.extend<TestFixtures & TestOptions, WorkerFixtures>(
     await browserServer.close();
   },
 
-  cdpEndpoint: async ({ }, use, testInfo) => {
-    let browserProcess: ChildProcessWithoutNullStreams | undefined;
+  cdpServer: async ({ mcpBrowser }, use, testInfo) => {
+    test.skip(!['chrome', 'msedge', 'chromium'].includes(mcpBrowser!), 'CDP is not supported for non-Chromium browsers');
 
-    await use(async port => {
-      if (!port)
-        port = 3200 + test.info().parallelIndex;
-      if (browserProcess)
-        return `http://localhost:${port}`;
-      browserProcess = spawn(chromium.executablePath(), [
-        `--user-data-dir=${testInfo.outputPath('user-data-dir')}`,
-        `--remote-debugging-port=${port}`,
-        `--no-first-run`,
-        `--no-sandbox`,
-        `--headless`,
-        '--use-mock-keychain',
-        `data:text/html,hello world`,
-      ], {
-        stdio: 'pipe',
-      });
-      await new Promise<void>(resolve => {
-        browserProcess!.stderr.on('data', data => {
-          if (data.toString().includes('DevTools listening on '))
-            resolve();
+    let browserContext: BrowserContext | undefined;
+    const port = 3200 + test.info().parallelIndex;
+    await use({
+      endpoint: `http://localhost:${port}`,
+      start: async () => {
+        browserContext = await chromium.launchPersistentContext(testInfo.outputPath('cdp-user-data-dir'), {
+          channel: mcpBrowser,
+          headless: true,
+          args: [
+            `--remote-debugging-port=${port}`,
+          ],
         });
-      });
-      return `http://localhost:${port}`;
-    });
-    await new Promise<void>(resolve => {
-      if (!browserProcess)
-        return resolve();
-      browserProcess.on('exit', () => resolve());
-      browserProcess.kill();
+        return browserContext;
+      }
     });
+    await browserContext?.close();
   },
 
   mcpHeadless: async ({ headless }, use) => {
@@ -138,14 +147,39 @@ export const test = baseTest.extend<TestFixtures & TestOptions, WorkerFixtures>(
 
   mcpMode: [undefined, { option: true }],
 
-  localOutputPath: async ({ mcpMode }, use, testInfo) => {
-    await use(filePath => {
-      test.skip(mcpMode === 'docker', 'Mounting files is not supported in docker mode');
-      return testInfo.outputPath(filePath);
+  startMcpExtension: async ({ mcpMode, mcpHeadless }, use) => {
+    let context: BrowserContext | undefined;
+    await use(async (relayServerURL: string) => {
+      if (mcpMode !== 'extension')
+        throw new Error('Must be running in MCP extension mode to use this fixture.');
+      const cdpPort = await findFreePort();
+      const pathToExtension = path.join(url.fileURLToPath(import.meta.url), '../../extension');
+      context = await chromium.launchPersistentContext('', {
+        headless: mcpHeadless,
+        args: [
+          `--disable-extensions-except=${pathToExtension}`,
+          `--load-extension=${pathToExtension}`,
+          '--enable-features=AllowContentInitiatedDataUrlNavigations',
+        ],
+        channel: 'chromium',
+        ...{ assistantMode: true, cdpPort },
+      });
+      const popupPage = await context.newPage();
+      const page = context.pages()[0];
+      await page.bringToFront();
+      // Do not auto dismiss dialogs.
+      page.on('dialog', () => { });
+      await expect.poll(() => context?.serviceWorkers()).toHaveLength(1);
+      // Connect to the relay server.
+      await popupPage.goto(new URL('/popup.html', context.serviceWorkers()[0].url()).toString());
+      await popupPage.getByRole('textbox', { name: 'Bridge Server URL:' }).clear();
+      await popupPage.getByRole('textbox', { name: 'Bridge Server URL:' }).fill(relayServerURL);
+      await popupPage.getByRole('button', { name: 'Share This Tab' }).click();
     });
+    await context?.close();
   },
 
-  _workerServers: [async ({}, use, workerInfo) => {
+  _workerServers: [async ({ }, use, workerInfo) => {
     const port = 8907 + workerInfo.workerIndex * 4;
     const server = await TestServer.create(port);
 
@@ -171,22 +205,77 @@ export const test = baseTest.extend<TestFixtures & TestOptions, WorkerFixtures>(
   },
 });
 
-function createTransport(args: string[], mcpMode: TestOptions['mcpMode']) {
+async function createTransport(args: string[], mcpMode: TestOptions['mcpMode']): Promise<{
+  transport: Transport,
+  stderr: Stream | null,
+  relayServerURL?: string,
+}> {
   // NOTE: Can be removed when we drop Node.js 18 support and changed to import.meta.filename.
   const __filename = url.fileURLToPath(import.meta.url);
   if (mcpMode === 'docker') {
     const dockerArgs = ['run', '--rm', '-i', '--network=host', '-v', `${test.info().project.outputDir}:/app/test-results`];
-    return new StdioClientTransport({
+    const transport = new StdioClientTransport({
       command: 'docker',
       args: [...dockerArgs, 'playwright-mcp-dev:latest', ...args],
     });
+    return {
+      transport,
+      stderr: transport.stderr,
+    };
   }
-  return new StdioClientTransport({
+  if (mcpMode === 'extension') {
+    const relay = fork(path.join(__filename, '../../cli.js'), [...args, '--extension', '--port=0'], {
+      stdio: 'pipe'
+    });
+    const cdpRelayServerReady = new ManualPromise<string>();
+    const sseEndpointPromise = new ManualPromise<string>();
+    let stderrBuffer = '';
+    relay.stderr!.on('data', data => {
+      stderrBuffer += data.toString();
+      const match = stderrBuffer.match(/Listening on (http:\/\/.*)/);
+      if (match)
+        sseEndpointPromise.resolve(match[1].toString());
+      const extensionMatch = stderrBuffer.match(/CDP relay server started on (ws:\/\/.*\/extension)/);
+      if (extensionMatch)
+        cdpRelayServerReady.resolve(extensionMatch[1].toString());
+    });
+    relay.on('exit', () => {
+      sseEndpointPromise.reject(new Error(`Process exited`));
+      cdpRelayServerReady.reject(new Error(`Process exited`));
+    });
+    const relayServerURL = await cdpRelayServerReady;
+    const sseEndpoint = await sseEndpointPromise;
+
+    const transport = new SSEClientTransport(new URL(sseEndpoint));
+    // We cannot just add  transport.onclose here as Client.connect() overrides it.
+    const origClose = transport.close;
+    transport.close = async () => {
+      await origClose.call(transport);
+      relay.kill();
+    };
+    return {
+      transport,
+      stderr: relay.stderr!,
+      relayServerURL,
+    };
+  }
+
+  const transport = new StdioClientTransport({
     command: 'node',
     args: [path.join(path.dirname(__filename), '../cli.js'), ...args],
     cwd: path.join(path.dirname(__filename), '..'),
-    env: process.env as Record<string, string>,
+    stderr: 'pipe',
+    env: {
+      ...process.env,
+      DEBUG: 'pw:mcp:test',
+      DEBUG_COLORS: '0',
+      DEBUG_HIDE_DATE: '1',
+    },
   });
+  return {
+    transport,
+    stderr: transport.stderr!,
+  };
 }
 
 type Response = Awaited<ReturnType<Client['callTool']>>;
@@ -242,3 +331,18 @@ export const expect = baseExpect.extend({
     };
   },
 });
+
+async function findFreePort(): Promise<number> {
+  return new Promise((resolve, reject) => {
+    const server = net.createServer();
+    server.listen(0, () => {
+      const { port } = server.address() as net.AddressInfo;
+      server.close(() => resolve(port));
+    });
+    server.on('error', reject);
+  });
+}
+
+export function formatOutput(output: string): string[] {
+  return output.split('\n').map(line => line.replace(/^pw:mcp:test /, '').replace(/user data dir.*/, 'user data dir').trim()).filter(Boolean);
+}

tests/launch.spec.ts

@@ -16,9 +16,12 @@
 
 import fs from 'fs';
 
-import { test, expect } from './fixtures.js';
+import { test, expect, formatOutput } from './fixtures.js';
 
-test('test reopen browser', async ({ client, server }) => {
+test.skip(({ mcpMode }) => mcpMode === 'extension', 'launch scenarios are not supported with --extension - the browser is already launched');
+
+test('test reopen browser', async ({ startClient, server, mcpMode }) => {
+  const { client, stderr } = await startClient();
   await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.HELLO_WORLD },
@@ -26,16 +29,37 @@ test('test reopen browser', async ({ client, server }) => {
 
   expect(await client.callTool({
     name: 'browser_close',
-  })).toContainTextContent('No open pages available');
+  })).toContainTextContent('Browser closed successfully.');
 
   expect(await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.HELLO_WORLD },
   })).toContainTextContent(`- generic [ref=e1]: Hello, world!`);
+
+  await client.close();
+
+  if (process.platform === 'win32')
+    return;
+
+  await expect.poll(() => formatOutput(stderr()), { timeout: 0 }).toEqual([
+    'create context',
+    'create browser context (persistent)',
+    'lock user data dir',
+    'close context',
+    'close browser context (persistent)',
+    'release user data dir',
+    'close browser context complete (persistent)',
+    'create browser context (persistent)',
+    'lock user data dir',
+    'close context',
+    'close browser context (persistent)',
+    'release user data dir',
+    'close browser context complete (persistent)',
+  ]);
 });
 
 test('executable path', async ({ startClient, server }) => {
-  const client = await startClient({ args: [`--executable-path=bogus`] });
+  const { client } = await startClient({ args: [`--executable-path=bogus`] });
   const response = await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.HELLO_WORLD },
@@ -53,7 +77,7 @@ test('persistent context', async ({ startClient, server }) => {
     </script>
   `, 'text/html');
 
-  const client = await startClient();
+  const { client } = await startClient();
   const response = await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.PREFIX },
@@ -66,7 +90,7 @@ test('persistent context', async ({ startClient, server }) => {
     name: 'browser_close',
   });
 
-  const client2 = await startClient();
+  const { client: client2 } = await startClient();
   const response2 = await client2.callTool({
     name: 'browser_navigate',
     arguments: { url: server.PREFIX },
@@ -85,18 +109,18 @@ test('isolated context', async ({ startClient, server }) => {
     </script>
   `, 'text/html');
 
-  const client = await startClient({ args: [`--isolated`] });
-  const response = await client.callTool({
+  const { client: client1 } = await startClient({ args: [`--isolated`] });
+  const response = await client1.callTool({
     name: 'browser_navigate',
     arguments: { url: server.PREFIX },
   });
   expect(response).toContainTextContent(`Storage: NO`);
 
-  await client.callTool({
+  await client1.callTool({
     name: 'browser_close',
   });
 
-  const client2 = await startClient({ args: [`--isolated`] });
+  const { client: client2 } = await startClient({ args: [`--isolated`] });
   const response2 = await client2.callTool({
     name: 'browser_navigate',
     arguments: { url: server.PREFIX },
@@ -104,8 +128,8 @@ test('isolated context', async ({ startClient, server }) => {
   expect(response2).toContainTextContent(`Storage: NO`);
 });
 
-test('isolated context with storage state', async ({ startClient, server, localOutputPath }) => {
-  const storageStatePath = localOutputPath('storage-state.json');
+test('isolated context with storage state', async ({ startClient, server }, testInfo) => {
+  const storageStatePath = testInfo.outputPath('storage-state.json');
   await fs.promises.writeFile(storageStatePath, JSON.stringify({
     origins: [
       {
@@ -123,7 +147,7 @@ test('isolated context with storage state', async ({ startClient, server, localO
     </script>
   `, 'text/html');
 
-  const client = await startClient({ args: [
+  const { client } = await startClient({ args: [
     `--isolated`,
     `--storage-state=${storageStatePath}`,
   ] });

tests/library.spec.ts

@@ -0,0 +1,28 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { test, expect } from './fixtures.js';
+import fs from 'node:fs/promises';
+import child_process from 'node:child_process';
+
+test('library can be used from CommonJS', { annotation: { type: 'issue', description: 'https://github.com/microsoft/playwright-mcp/issues/456' } }, async ({}, testInfo) => {
+  const file = testInfo.outputPath('main.cjs');
+  await fs.writeFile(file, `
+    import('@playwright/mcp')
+      .then(playwrightMCP => playwrightMCP.createConnection())
+      .then(() => console.log('OK'));
+ `);
+  expect(child_process.execSync(`node ${file}`, { encoding: 'utf-8' })).toContain('OK');
+});

tests/pdf.spec.ts

@@ -19,7 +19,7 @@ import fs from 'fs';
 import { test, expect } from './fixtures.js';
 
 test('save as pdf unavailable', async ({ startClient, server }) => {
-  const client = await startClient({ args: ['--caps="no-pdf"'] });
+  const { client } = await startClient({ args: ['--caps="no-pdf"'] });
   await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.HELLO_WORLD },
@@ -30,7 +30,11 @@ test('save as pdf unavailable', async ({ startClient, server }) => {
   })).toHaveTextContent(/Tool \"browser_pdf_save\" not found/);
 });
 
-test('save as pdf', async ({ client, mcpBrowser, server }) => {
+test('save as pdf', async ({ startClient, mcpBrowser, server }, testInfo) => {
+  const { client } = await startClient({
+    config: { outputDir: testInfo.outputPath('output') },
+  });
+
   test.skip(!!mcpBrowser && !['chromium', 'chrome', 'msedge'].includes(mcpBrowser), 'Save as PDF is only supported in Chromium.');
 
   expect(await client.callTool({
@@ -44,10 +48,10 @@ test('save as pdf', async ({ client, mcpBrowser, server }) => {
   expect(response).toHaveTextContent(/Save page as.*page-[^:]+.pdf/);
 });
 
-test('save as pdf (filename: output.pdf)', async ({ startClient, mcpBrowser, server, localOutputPath }) => {
+test('save as pdf (filename: output.pdf)', async ({ startClient, mcpBrowser, server }, testInfo) => {
+  const outputDir = testInfo.outputPath('output');
   test.skip(!!mcpBrowser && !['chromium', 'chrome', 'msedge'].includes(mcpBrowser), 'Save as PDF is only supported in Chromium.');
-  const outputDir = localOutputPath('output');
-  const client = await startClient({
+  const { client } = await startClient({
     config: { outputDir },
   });
 
@@ -73,6 +77,7 @@ test('save as pdf (filename: output.pdf)', async ({ startClient, mcpBrowser, ser
   const files = [...fs.readdirSync(outputDir)];
 
   expect(fs.existsSync(outputDir)).toBeTruthy();
-  expect(files).toHaveLength(1);
-  expect(files[0]).toMatch(/^output.pdf$/);
+  const pdfFiles = files.filter(f => f.endsWith('.pdf'));
+  expect(pdfFiles).toHaveLength(1);
+  expect(pdfFiles[0]).toMatch(/^output.pdf$/);
 });

tests/request-blocking.spec.ts

@@ -37,7 +37,7 @@ test('default to allow all', async ({ server, client }) => {
 });
 
 test('blocked works', async ({ startClient }) => {
-  const client = await startClient({
+  const { client } = await startClient({
     args: ['--blocked-origins', 'microsoft.com;example.com;playwright.dev']
   });
   const result = await fetchPage(client, 'https://example.com/');
@@ -46,7 +46,7 @@ test('blocked works', async ({ startClient }) => {
 
 test('allowed works', async ({ server, startClient }) => {
   server.setContent('/ppp', 'content:PPP', 'text/html');
-  const client = await startClient({
+  const { client } = await startClient({
     args: ['--allowed-origins', `microsoft.com;${new URL(server.PREFIX).host};playwright.dev`]
   });
   const result = await fetchPage(client, server.PREFIX + 'ppp');
@@ -54,7 +54,7 @@ test('allowed works', async ({ server, startClient }) => {
 });
 
 test('blocked takes precedence', async ({ startClient }) => {
-  const client = await startClient({
+  const { client } = await startClient({
     args: [
       '--blocked-origins', 'example.com',
       '--allowed-origins', 'example.com',
@@ -65,7 +65,7 @@ test('blocked takes precedence', async ({ startClient }) => {
 });
 
 test('allowed without blocked blocks all non-explicitly specified origins', async ({ startClient }) => {
-  const client = await startClient({
+  const { client } = await startClient({
     args: ['--allowed-origins', 'playwright.dev'],
   });
   const result = await fetchPage(client, 'https://example.com/');
@@ -74,7 +74,7 @@ test('allowed without blocked blocks all non-explicitly specified origins', asyn
 
 test('blocked without allowed allows non-explicitly specified origins', async ({ server, startClient }) => {
   server.setContent('/ppp', 'content:PPP', 'text/html');
-  const client = await startClient({
+  const { client } = await startClient({
     args: ['--blocked-origins', 'example.com'],
   });
   const result = await fetchPage(client, server.PREFIX + 'ppp');

tests/screenshot.spec.ts

@@ -18,7 +18,10 @@ import fs from 'fs';
 
 import { test, expect } from './fixtures.js';
 
-test('browser_take_screenshot (viewport)', async ({ client, server }) => {
+test('browser_take_screenshot (viewport)', async ({ startClient, server }, testInfo) => {
+  const { client } = await startClient({
+    config: { outputDir: testInfo.outputPath('output') },
+  });
   expect(await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.HELLO_WORLD },
@@ -41,7 +44,10 @@ test('browser_take_screenshot (viewport)', async ({ client, server }) => {
   });
 });
 
-test('browser_take_screenshot (element)', async ({ client, server }) => {
+test('browser_take_screenshot (element)', async ({ startClient, server }, testInfo) => {
+  const { client } = await startClient({
+    config: { outputDir: testInfo.outputPath('output') },
+  });
   expect(await client.callTool({
     name: 'browser_navigate',
     arguments: { url: server.HELLO_WORLD },
@@ -68,10 +74,10 @@ test('browser_take_screenshot (element)', async ({ client, server }) => {
   });
 });
 
-test('--output-dir should work', async ({ startClient, localOutputPath, server }) => {
-  const outputDir = localOutputPath('output');
-  const client = await startClient({
-    args: ['--output-dir', outputDir],
+test('--output-dir should work', async ({ startClient, server }, testInfo) => {
+  const outputDir = testInfo.outputPath('output');
+  const { client } = await startClient({
+    config: { outputDir },
   });
   expect(await client.callTool({
     name: 'browser_navigate',
@@ -83,14 +89,16 @@ test('--output-dir should work', async ({ startClient, localOutputPath, server }
   });
 
   expect(fs.existsSync(outputDir)).toBeTruthy();
-  expect([...fs.readdirSync(outputDir)]).toHaveLength(1);
+  const files = [...fs.readdirSync(outputDir)].filter(f => f.endsWith('.jpeg'));
+  expect(files).toHaveLength(1);
+  expect(files[0]).toMatch(/^page-\d{4}-\d{2}-\d{2}T\d{2}-\d{2}-\d{2}-\d{3}Z\.jpeg$/);
 });
 
 for (const raw of [undefined, true]) {
-  test(`browser_take_screenshot (raw: ${raw})`, async ({ startClient, localOutputPath, server }) => {
+  test(`browser_take_screenshot (raw: ${raw})`, async ({ startClient, server }, testInfo) => {
+    const outputDir = testInfo.outputPath('output');
     const ext = raw ? 'png' : 'jpeg';
-    const outputDir = localOutputPath('output');
-    const client = await startClient({
+    const { client } = await startClient({
       config: { outputDir },
     });
     expect(await client.callTool({
@@ -117,7 +125,7 @@ for (const raw of [undefined, true]) {
       ],
     });
 
-    const files = [...fs.readdirSync(outputDir)];
+    const files = [...fs.readdirSync(outputDir)].filter(f => f.endsWith(`.${ext}`));
 
     expect(fs.existsSync(outputDir)).toBeTruthy();
     expect(files).toHaveLength(1);
@@ -128,9 +136,9 @@ for (const raw of [undefined, true]) {
 
 }
 
-test('browser_take_screenshot (filename: "output.jpeg")', async ({ startClient, localOutputPath, server }) => {
-  const outputDir = localOutputPath('output');
-  const client = await startClient({
+test('browser_take_screenshot (filename: "output.jpeg")', async ({ startClient, server }, testInfo) => {
+  const outputDir = testInfo.outputPath('output');
+  const { client } = await startClient({
     config: { outputDir },
   });
   expect(await client.callTool({
@@ -157,17 +165,19 @@ test('browser_take_screenshot (filename: "output.jpeg")', async ({ startClient,
     ],
   });
 
-  const files = [...fs.readdirSync(outputDir)];
+  const files = [...fs.readdirSync(outputDir)].filter(f => f.endsWith('.jpeg'));
 
   expect(fs.existsSync(outputDir)).toBeTruthy();
   expect(files).toHaveLength(1);
-  expect(files[0]).toMatch(/^output.jpeg$/);
+  expect(files[0]).toMatch(/^output\.jpeg$/);
 });
 
-test('browser_take_screenshot (noImageResponses)', async ({ startClient, server }) => {
-  const client = await startClient({
+test('browser_take_screenshot (imageResponses=omit)', async ({ startClient, server }, testInfo) => {
+  const outputDir = testInfo.outputPath('output');
+  const { client } = await startClient({
     config: {
-      noImageResponses: true,
+      outputDir,
+      imageResponses: 'omit',
     },
   });
 
@@ -192,8 +202,13 @@ test('browser_take_screenshot (noImageResponses)', async ({ startClient, server
   });
 });
 
-test('browser_take_screenshot (cursor)', async ({ startClient, server }) => {
-  const client = await startClient({ clientName: 'cursor:vscode' });
+test('browser_take_screenshot (cursor)', async ({ startClient, server }, testInfo) => {
+  const outputDir = testInfo.outputPath('output');
+
+  const { client } = await startClient({
+    clientName: 'cursor:vscode',
+    config: { outputDir },
+  });
 
   expect(await client.callTool({
     name: 'browser_navigate',

tests/sse.spec.ts

@@ -14,90 +14,235 @@
  * limitations under the License.
  */
 
+import fs from 'node:fs';
 import url from 'node:url';
-import http from 'node:http';
-import { spawn } from 'node:child_process';
+
+import { ChildProcess, spawn } from 'node:child_process';
 import path from 'node:path';
-import type { AddressInfo } from 'node:net';
 import { SSEClientTransport } from '@modelcontextprotocol/sdk/client/sse.js';
-import { SSEServerTransport } from '@modelcontextprotocol/sdk/server/sse.js';
 import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js';
 import { Client } from '@modelcontextprotocol/sdk/client/index.js';
 
-import { createConnection } from '@playwright/mcp';
-
 import { test as baseTest, expect } from './fixtures.js';
+import type { Config } from '../config.d.ts';
 
 // NOTE: Can be removed when we drop Node.js 18 support and changed to import.meta.filename.
 const __filename = url.fileURLToPath(import.meta.url);
 
-const test = baseTest.extend<{ serverEndpoint: string }>({
-  serverEndpoint: async ({}, use) => {
-    const cp = spawn('node', [path.join(path.dirname(__filename), '../cli.js'), '--port', '0'], { stdio: 'pipe' });
-    try {
-      let stdout = '';
-      const url = await new Promise<string>(resolve => cp.stdout?.on('data', data => {
-        stdout += data.toString();
-        const match = stdout.match(/Listening on (http:\/\/.*)/);
+baseTest.skip(({ mcpMode }) => mcpMode === 'extension', 'Extension tests run via SSE anyways');
+
+const test = baseTest.extend<{ serverEndpoint: (options?: { args?: string[], noPort?: boolean }) => Promise<{ url: URL, stderr: () => string }> }>({
+  serverEndpoint: async ({ mcpHeadless }, use, testInfo) => {
+    let cp: ChildProcess | undefined;
+    const userDataDir = testInfo.outputPath('user-data-dir');
+    await use(async (options?: { args?: string[], noPort?: boolean }) => {
+      if (cp)
+        throw new Error('Process already running');
+
+      cp = spawn('node', [
+        path.join(path.dirname(__filename), '../cli.js'),
+        ...(options?.noPort ? [] : ['--port=0']),
+        '--user-data-dir=' + userDataDir,
+        ...(mcpHeadless ? ['--headless'] : []),
+        ...(options?.args || []),
+      ], {
+        stdio: 'pipe',
+        env: {
+          ...process.env,
+          DEBUG: 'pw:mcp:test',
+          DEBUG_COLORS: '0',
+          DEBUG_HIDE_DATE: '1',
+        },
+      });
+      let stderr = '';
+      const url = await new Promise<string>(resolve => cp!.stderr?.on('data', data => {
+        stderr += data.toString();
+        const match = stderr.match(/Listening on (http:\/\/.*)/);
         if (match)
           resolve(match[1]);
       }));
 
-      await use(url);
-    } finally {
-      cp.kill();
-    }
+      return { url: new URL(url), stderr: () => stderr };
+    });
+    cp?.kill('SIGTERM');
   },
 });
 
 test('sse transport', async ({ serverEndpoint }) => {
-  const transport = new SSEClientTransport(new URL(serverEndpoint));
+  const { url } = await serverEndpoint();
+  const transport = new SSEClientTransport(url);
   const client = new Client({ name: 'test', version: '1.0.0' });
   await client.connect(transport);
   await client.ping();
 });
 
+test('sse transport (config)', async ({ serverEndpoint }) => {
+  const config: Config = {
+    server: {
+      port: 0,
+    }
+  };
+  const configFile = test.info().outputPath('config.json');
+  await fs.promises.writeFile(configFile, JSON.stringify(config, null, 2));
+
+  const { url } = await serverEndpoint({ noPort: true, args: ['--config=' + configFile] });
+  const transport = new SSEClientTransport(url);
+  const client = new Client({ name: 'test', version: '1.0.0' });
+  await client.connect(transport);
+  await client.ping();
+});
+
+test('sse transport browser lifecycle (isolated)', async ({ serverEndpoint, server }) => {
+  const { url, stderr } = await serverEndpoint({ args: ['--isolated'] });
+
+  const transport1 = new SSEClientTransport(url);
+  const client1 = new Client({ name: 'test', version: '1.0.0' });
+  await client1.connect(transport1);
+  await client1.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+  await client1.close();
+
+  const transport2 = new SSEClientTransport(url);
+  const client2 = new Client({ name: 'test', version: '1.0.0' });
+  await client2.connect(transport2);
+  await client2.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+  await client2.close();
+
+  await expect(async () => {
+    const lines = stderr().split('\n');
+    expect(lines.filter(line => line.match(/create SSE session/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/delete SSE session/)).length).toBe(2);
+
+    expect(lines.filter(line => line.match(/create context/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/close context/)).length).toBe(2);
+
+    expect(lines.filter(line => line.match(/create browser context \(isolated\)/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/close browser context \(isolated\)/)).length).toBe(2);
+
+    expect(lines.filter(line => line.match(/obtain browser \(isolated\)/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/close browser \(isolated\)/)).length).toBe(2);
+  }).toPass();
+});
+
+test('sse transport browser lifecycle (isolated, multiclient)', async ({ serverEndpoint, server }) => {
+  const { url, stderr } = await serverEndpoint({ args: ['--isolated'] });
+
+  const transport1 = new SSEClientTransport(url);
+  const client1 = new Client({ name: 'test', version: '1.0.0' });
+  await client1.connect(transport1);
+  await client1.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+
+  const transport2 = new SSEClientTransport(url);
+  const client2 = new Client({ name: 'test', version: '1.0.0' });
+  await client2.connect(transport2);
+  await client2.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+  await client1.close();
+
+  const transport3 = new SSEClientTransport(url);
+  const client3 = new Client({ name: 'test', version: '1.0.0' });
+  await client3.connect(transport3);
+  await client3.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+
+  await client2.close();
+  await client3.close();
+
+  await expect(async () => {
+    const lines = stderr().split('\n');
+    expect(lines.filter(line => line.match(/create SSE session/)).length).toBe(3);
+    expect(lines.filter(line => line.match(/delete SSE session/)).length).toBe(3);
+
+    expect(lines.filter(line => line.match(/create context/)).length).toBe(3);
+    expect(lines.filter(line => line.match(/close context/)).length).toBe(3);
+
+    expect(lines.filter(line => line.match(/create browser context \(isolated\)/)).length).toBe(3);
+    expect(lines.filter(line => line.match(/close browser context \(isolated\)/)).length).toBe(3);
+
+    expect(lines.filter(line => line.match(/obtain browser \(isolated\)/)).length).toBe(1);
+    expect(lines.filter(line => line.match(/close browser \(isolated\)/)).length).toBe(1);
+  }).toPass();
+});
+
+test('sse transport browser lifecycle (persistent)', async ({ serverEndpoint, server }) => {
+  const { url, stderr } = await serverEndpoint();
+
+  const transport1 = new SSEClientTransport(url);
+  const client1 = new Client({ name: 'test', version: '1.0.0' });
+  await client1.connect(transport1);
+  await client1.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+  await client1.close();
+
+  const transport2 = new SSEClientTransport(url);
+  const client2 = new Client({ name: 'test', version: '1.0.0' });
+  await client2.connect(transport2);
+  await client2.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+  await client2.close();
+
+  await expect(async () => {
+    const lines = stderr().split('\n');
+    expect(lines.filter(line => line.match(/create SSE session/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/delete SSE session/)).length).toBe(2);
+
+    expect(lines.filter(line => line.match(/create context/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/close context/)).length).toBe(2);
+
+    expect(lines.filter(line => line.match(/create browser context \(persistent\)/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/close browser context \(persistent\)/)).length).toBe(2);
+
+    expect(lines.filter(line => line.match(/lock user data dir/)).length).toBe(2);
+    expect(lines.filter(line => line.match(/release user data dir/)).length).toBe(2);
+  }).toPass();
+});
+
+test('sse transport browser lifecycle (persistent, multiclient)', async ({ serverEndpoint, server }) => {
+  const { url } = await serverEndpoint();
+
+  const transport1 = new SSEClientTransport(url);
+  const client1 = new Client({ name: 'test', version: '1.0.0' });
+  await client1.connect(transport1);
+  await client1.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+
+  const transport2 = new SSEClientTransport(url);
+  const client2 = new Client({ name: 'test', version: '1.0.0' });
+  await client2.connect(transport2);
+  const response = await client2.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  });
+  expect(response.isError).toBe(true);
+  expect(response.content?.[0].text).toContain('use --isolated to run multiple instances of the same browser');
+
+  await client1.close();
+  await client2.close();
+});
+
 test('streamable http transport', async ({ serverEndpoint }) => {
-  const transport = new StreamableHTTPClientTransport(new URL('/mcp', serverEndpoint));
+  const { url } = await serverEndpoint();
+  const transport = new StreamableHTTPClientTransport(new URL('/mcp', url));
   const client = new Client({ name: 'test', version: '1.0.0' });
   await client.connect(transport);
   await client.ping();
   expect(transport.sessionId, 'has session support').toBeDefined();
 });
-
-test('sse transport via public API', async ({ server }) => {
-  const sessions = new Map<string, SSEServerTransport>();
-  const mcpServer = http.createServer(async (req, res) => {
-    if (req.method === 'GET') {
-      const connection = await createConnection({ browser: { launchOptions: { headless: true } } });
-      const transport = new SSEServerTransport('/sse', res);
-      sessions.set(transport.sessionId, transport);
-      await connection.connect(transport);
-    } else if (req.method === 'POST') {
-      const url = new URL(`http://localhost${req.url}`);
-      const sessionId = url.searchParams.get('sessionId');
-      if (!sessionId) {
-        res.statusCode = 400;
-        return res.end('Missing sessionId');
-      }
-      const transport = sessions.get(sessionId);
-      if (!transport) {
-        res.statusCode = 404;
-        return res.end('Session not found');
-      }
-      void transport.handlePostMessage(req, res);
-    }
-  });
-  await new Promise<void>(resolve => mcpServer.listen(0, () => resolve()));
-  const serverUrl = `http://localhost:${(mcpServer.address() as AddressInfo).port}/sse`;
-  const transport = new SSEClientTransport(new URL(serverUrl));
-  const client = new Client({ name: 'test', version: '1.0.0' });
-  await client.connect(transport);
-  await client.ping();
-  expect(await client.callTool({
-    name: 'browser_navigate',
-    arguments: { url: server.HELLO_WORLD },
-  })).toContainTextContent(`- generic [ref=e1]: Hello, world!`);
-  await client.close();
-  mcpServer.close();
-});

tests/tabs.spec.ts

@@ -14,8 +14,6 @@
  * limitations under the License.
  */
 
-import { chromium } from 'playwright';
-
 import { test, expect } from './fixtures.js';
 
 import type { Client } from '@modelcontextprotocol/sdk/client/index.js';
@@ -29,6 +27,8 @@ async function createTab(client: Client, title: string, body: string) {
   });
 }
 
+test.skip(({ mcpMode }) => mcpMode === 'extension', 'Multi-tab scenarios are not supported with --extension');
+
 test('list initial tabs', async ({ client }) => {
   expect(await client.callTool({
     name: 'browser_tab_list',
@@ -139,17 +139,14 @@ test('close tab', async ({ client }) => {
 \`\`\``);
 });
 
-test('reuse first tab when navigating', async ({ startClient, cdpEndpoint, server }) => {
-  server.setContent('/', `<title>Title</title><body>Body</body>`, 'text/html');
+test('reuse first tab when navigating', async ({ startClient, cdpServer, server }) => {
+  const browserContext = await cdpServer.start();
+  const pages = browserContext.pages();
 
-  const browser = await chromium.connectOverCDP(await cdpEndpoint());
-  const [context] = browser.contexts();
-  const pages = context.pages();
-
-  const client = await startClient({ args: [`--cdp-endpoint=${await cdpEndpoint()}`] });
+  const { client } = await startClient({ args: [`--cdp-endpoint=${cdpServer.endpoint}`] });
   await client.callTool({
     name: 'browser_navigate',
-    arguments: { url: server.PREFIX },
+    arguments: { url: server.HELLO_WORLD },
   });
 
   expect(pages.length).toBe(1);

tests/trace.spec.ts

@@ -0,0 +1,37 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import fs from 'fs';
+import path from 'path';
+
+import { test, expect } from './fixtures.js';
+
+test('check that trace is saved', async ({ startClient, server, mcpMode }, testInfo) => {
+  test.fixme(mcpMode === 'extension', 'Tracing is not supported via CDP');
+
+  const outputDir = testInfo.outputPath('output');
+
+  const { client } = await startClient({
+    args: ['--save-trace', `--output-dir=${outputDir}`],
+  });
+
+  expect(await client.callTool({
+    name: 'browser_navigate',
+    arguments: { url: server.HELLO_WORLD },
+  })).toContainTextContent(`Navigate to http://localhost`);
+
+  expect(fs.existsSync(path.join(outputDir, 'traces', 'trace.trace'))).toBeTruthy();
+});