PlayMCP Browser Automation Server

Instructions

Implementation Reference

• src/controllers/playwright.ts:694-706 (handler)

  The core handler function implementing waitForSelector using Playwright's page.waitForSelector method, with error handling and logging.

  async waitForSelector(selector: string, timeout: number = 30000): Promise<void> {
    try {
      if (!this.isInitialized() || !this.state.page) {
        throw new Error('Browser not initialized');
      }
      this.log('Waiting for selector', { selector, timeout });
      await this.state.page.waitForSelector(selector, { timeout });
      this.log('Selector found');
    } catch (error: any) {
      console.error('Wait for selector error:', error);
      throw new BrowserError('Selector not found within timeout', 'Check if the selector appears on the page');
    }
  }

• src/server.ts:343-357 (schema)

  Input schema definition for the waitForSelector tool, specifying selector (required) and optional timeout.

  const WAIT_FOR_SELECTOR_TOOL: Tool = {
    name: "waitForSelector",
    description: "Wait for a specific selector to appear on the page",
    inputSchema: {
      type: "object",
      properties: {
        selector: { type: "string" },
        timeout: { 
          type: "number",
          description: "Timeout in milliseconds (default: 30000)"
        }
      },
      required: ["selector"]
    }
  };

• src/server.ts:541-541 (registration)

  Registration of the waitForSelector tool in the tools object passed to MCP server capabilities.

  waitForSelector: WAIT_FOR_SELECTOR_TOOL,

• src/server.ts:860-871 (registration)

  Dispatch handler in the callTool request handler switch statement that invokes the playwrightController's waitForSelector method.

  case 'waitForSelector': {
    if (!args.selector) {
      return {
        content: [{ type: "text", text: "Selector is required" }],
        isError: true
      };
    }
    await playwrightController.waitForSelector(args.selector as string, args.timeout as number);
    return {
      content: [{ type: "text", text: "Selector found successfully" }]
    };
  }