cdp_send

Implementation Reference

• server.js:41-59 (handler)

  Handler function for the 'cdp_send' tool. Ensures browser/CDP session is ready, sends the specified CDP method with params, returns JSON stringified result or error.

  async ({ method, params }) => {
    const { cdp } = await ensureBrowser();
    try {
      const result = await cdp.send(method, params || {});
      return {
        content: [{ type: "text", text: JSON.stringify(result, null, 2) }],
      };
    } catch (error) {
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify({ error: error.message }, null, 2),
          },
        ],
        isError: true,
      };
    }
  }

• server.js:32-40 (schema)

  Input schema for 'cdp_send' tool using Zod: required 'method' string and optional 'params' object.

  {
    method: z
      .string()
      .describe("CDP method (e.g., 'Page.navigate', 'DOM.getDocument', 'Runtime.evaluate')"),
    params: z
      .record(z.unknown())
      .optional()
      .describe("Parameters object for the CDP method"),
  },

• server.js:28-60 (registration)

  Registration of the 'cdp_send' tool with MCP server.tool, including schema and handler.

  // Core tool: Raw CDP method - call ANY Chrome DevTools Protocol method
  // Reference: https://chromedevtools.github.io/devtools-protocol/
  server.tool(
    "cdp_send",
    {
      method: z
        .string()
        .describe("CDP method (e.g., 'Page.navigate', 'DOM.getDocument', 'Runtime.evaluate')"),
      params: z
        .record(z.unknown())
        .optional()
        .describe("Parameters object for the CDP method"),
    },
    async ({ method, params }) => {
      const { cdp } = await ensureBrowser();
      try {
        const result = await cdp.send(method, params || {});
        return {
          content: [{ type: "text", text: JSON.stringify(result, null, 2) }],
        };
      } catch (error) {
        return {
          content: [
            {
              type: "text",
              text: JSON.stringify({ error: error.message }, null, 2),
            },
          ],
          isError: true,
        };
      }
    }
  );

• server.js:16-26 (helper)

  Helper function ensureBrowser() that launches Chromium browser, creates a page, and initializes CDP session if not already done. Used by cdp_send handler.

  async function ensureBrowser() {
    if (!browser) {
      browser = await chromium.launch({
        headless: false,
        args: ["--disable-web-security", "--allow-running-insecure-content"],
      });
      page = await browser.newPage();
      cdp = await page.context().newCDPSession(page);
    }
    return { browser, page, cdp };
  }