chore(cli): "info" method that returns the version

This will be used for compatibility checks later on.

Drive-by: remove `sessionConfig` from the mcp config,
leave it only for the cli daemon.

Author: dgozman

packages/playwright/src/cli/client/registry.ts

@@ -28,6 +28,10 @@ export type ClientInfo = {
   workspaceDir: string | undefined;
 };
 
+export type ServerInfo = {
+  version: string;
+};
+
 export type SessionConfig = {
   name: string;
   version: string;

packages/playwright/src/cli/client/session.ts

@@ -173,7 +173,7 @@ to restart the browser session.`);
     if (!socket)
       socket = await this._startDaemon();
 
-    this._connection = new SocketConnection(socket, this.config.version);
+    this._connection = new SocketConnection(socket);
     this._connection.onmessage = message => this._onMessage(message);
     this._connection.onclose = () => this.disconnect();
     return this._connection;

packages/playwright/src/cli/client/socketConnection.ts

@@ -19,15 +19,12 @@ import net from 'net';
 export class SocketConnection {
   private _socket: net.Socket;
   private _pendingBuffers: Buffer[] = [];
-  private _version: string;
 
   onclose?: () => void;
   onmessage?: (message: any) => void;
-  onversionerror?: (id: number, versions: { expected: string, received: string }) => boolean;
 
-  constructor(socket: net.Socket, version: string) {
+  constructor(socket: net.Socket) {
     this._socket = socket;
-    this._version = version;
     socket.on('data', buffer => this._onData(buffer));
     socket.on('close', () => {
       this.onclose?.();
@@ -39,7 +36,7 @@ export class SocketConnection {
 
   async send(message: { id: number, error?: string, result?: any }) {
     await new Promise((resolve, reject) => {
-      this._socket.write(`${JSON.stringify({ ...message, version: this._version })}\n`, error => {
+      this._socket.write(`${JSON.stringify(message)}\n`, error => {
         if (error)
           reject(error);
         else
@@ -76,10 +73,6 @@ export class SocketConnection {
   private _dispatchMessage(message: string) {
     try {
       const parsedMessage = JSON.parse(message);
-      if (parsedMessage.version !== this._version) {
-        if (this.onversionerror?.(parsedMessage.id, { expected: this._version, received: parsedMessage.version }))
-          return;
-      }
       this.onmessage?.(parsedMessage);
     } catch (e) {
       // eslint-disable-next-line no-console

packages/playwright/src/cli/daemon/daemon.ts

@@ -31,6 +31,7 @@ import { parseCommand } from './command';
 import type * as mcp from '../../mcp/sdk/exports';
 import type { BrowserContextFactory } from '../../mcp/browser/browserContextFactory';
 import type { FullConfig } from '../../mcp/browser/config';
+import type { ServerInfo, SessionConfig } from '../client/registry';
 
 const daemonDebug = debug('pw:daemon');
 
@@ -45,11 +46,11 @@ async function socketExists(socketPath: string): Promise<boolean> {
 }
 
 export async function startMcpDaemonServer(
-  config: FullConfig,
+  mcpConfig: FullConfig,
+  sessionConfig: SessionConfig,
   contextFactory: BrowserContextFactory,
 ): Promise<string> {
-  const sessionConfig = config.sessionConfig!;
-  const { socketPath, version } = sessionConfig;
+  const { socketPath } = sessionConfig;
   // Clean up existing socket file on Unix
   if (os.platform() !== 'win32' && await socketExists(socketPath)) {
     daemonDebug(`Socket already exists, removing: ${socketPath}`);
@@ -81,7 +82,7 @@ export async function startMcpDaemonServer(
   const existingContextFactory = {
     createContext: () => Promise.resolve({ browserContext, close }),
   };
-  const backend = new BrowserServerBackend(config, existingContextFactory, { allTools: true });
+  const backend = new BrowserServerBackend(mcpConfig, existingContextFactory, { allTools: true });
   await backend.initialize?.(clientInfo);
 
   await fs.mkdir(path.dirname(socketPath), { recursive: true });
@@ -94,7 +95,7 @@ export async function startMcpDaemonServer(
 
   const server = net.createServer(socket => {
     daemonDebug('new client connection');
-    const connection = new SocketConnection(socket, version);
+    const connection = new SocketConnection(socket);
     connection.onclose = () => {
       daemonDebug('client disconnected');
     };
@@ -114,6 +115,9 @@ export async function startMcpDaemonServer(
             toolParams._meta = { cwd: params.cwd };
           const response = await backend.callTool(toolName, toolParams);
           await connection.send({ id, result: formatResult(response) });
+        } else if (method === 'info') {
+          const info: ServerInfo = { version: sessionConfig.version };
+          await connection.send({ id, result: info });
         } else {
           throw new Error(`Unknown method: ${method}`);
         }

packages/playwright/src/cli/daemon/program.ts

@@ -37,16 +37,17 @@ export function decorateCLICommand(command: Command, version: string) {
         options.chromiumSandbox = options.chromiumSandbox === true ? undefined : false;
         setupExitWatchdog();
 
-        const config = await resolveCLIConfig(options.daemonSession);
-        const browserContextFactory = contextFactory(config);
-        const extensionContextFactory = new ExtensionContextFactory(config.browser.launchOptions.channel || 'chrome', config.browser.userDataDir, config.browser.launchOptions.executablePath);
+        const sessionConfig = await fs.promises.readFile(options.daemonSession, 'utf-8').then(data => JSON.parse(data) as SessionConfig);
+        const mcpConfig = await resolveCLIConfig(sessionConfig);
+        const browserContextFactory = contextFactory(mcpConfig);
+        const extensionContextFactory = new ExtensionContextFactory(mcpConfig.browser.launchOptions.channel || 'chrome', mcpConfig.browser.userDataDir, mcpConfig.browser.launchOptions.executablePath);
 
-        const cf = config.extension ? extensionContextFactory : browserContextFactory;
+        const cf = mcpConfig.extension ? extensionContextFactory : browserContextFactory;
         try {
-          const socketPath = await startMcpDaemonServer(config, cf);
+          const socketPath = await startMcpDaemonServer(mcpConfig, sessionConfig, cf);
           console.log(`### Config`);
           console.log('```json');
-          console.log(JSON.stringify(config, null, 2));
+          console.log(JSON.stringify(mcpConfig, null, 2));
           console.log('```');
           console.log(`### Success\nDaemon listening on ${socketPath}`);
           console.log('<EOF>');
@@ -58,8 +59,7 @@ export function decorateCLICommand(command: Command, version: string) {
       });
 }
 
-export async function resolveCLIConfig(daemonSession: string): Promise<FullConfig> {
-  const sessionConfig = await fs.promises.readFile(daemonSession, 'utf-8').then(data => JSON.parse(data) as SessionConfig);
+async function resolveCLIConfig(sessionConfig: SessionConfig): Promise<FullConfig> {
   const daemonOverrides = configFromCLIOptions({
     config: sessionConfig.cli.config,
     browser: sessionConfig.cli.browser,
@@ -96,9 +96,8 @@ export async function resolveCLIConfig(daemonSession: string): Promise<FullConfi
   }
 
   result.configFile = configFile;
-  result.sessionConfig = sessionConfig;
   result.skillMode = true;
-  if (result.sessionConfig && result.browser.launchOptions.headless !== false)
+  if (result.browser.launchOptions.headless !== false)
     result.browser.contextOptions.viewport ??= { width: 1280, height: 720 };
 
   await validateConfig(result);

packages/playwright/src/mcp/browser/config.ts

@@ -134,7 +134,6 @@ export type FullConfig = Config & {
   },
   skillMode?: boolean;
   configFile?: string;
-  sessionConfig?: SessionConfig;
 };
 
 export async function resolveConfig(config: Config): Promise<FullConfig> {