// Minimal CDP MCP Server - Maximum flexibility browser control
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { chromium } from "playwright";
import { z } from "zod";
const server = new McpServer({
name: "browser-cdp",
version: "1.0.0",
});
let browser = null;
let page = null;
let cdp = null;
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 };
}
// 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,
};
}
}
);
// Convenience: Take screenshot (returns base64 image)
server.tool(
"screenshot",
{
format: z.enum(["png", "jpeg"]).optional().describe("Image format"),
fullPage: z.boolean().optional().describe("Capture full scrollable page"),
},
async ({ format = "png", fullPage = false }) => {
const { page } = await ensureBrowser();
const buffer = await page.screenshot({ type: format, fullPage });
return {
content: [
{
type: "image",
data: buffer.toString("base64"),
mimeType: `image/${format}`,
},
],
};
}
);
// Convenience: Get current URL
server.tool("get_url", {}, async () => {
const { page } = await ensureBrowser();
return { content: [{ type: "text", text: page.url() }] };
});
// Convenience: Close browser
server.tool("close_browser", {}, async () => {
if (browser) {
await browser.close();
browser = null;
page = null;
cdp = null;
}
return { content: [{ type: "text", text: "Browser closed" }] };
});
async function main() {
const transport = new StdioServerTransport();
await server.connect(transport);
}
main().catch(console.error);
