Chrome DevTools MCP Server Setup

Chrome DevTools Protocol (CDP) gives AI agents a real browser — navigate, query, screenshot, and interact with any web page using MCP tool calls.

Prerequisites

• Google Chrome (desktop) or Chromium
• A Molecule AI workspace

Start Chrome with Remote Debugging

Chrome exposes CDP over a WebSocket at a configurable port. Start Chrome with remote debugging enabled:

# macOS
/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome \
  --remote-debugging-port=9222 \
  --user-data-dir=/tmp/chrome-debug

# Linux
google-chrome --remote-debugging-port=9222 --user-data-dir=/tmp/chrome-debug

# Windows
chrome.exe --remote-debugging-port=9222 --user-data-dir="C:\\tmp\\chrome-debug"

To run headless (no visible window):

google-chrome \
  --headless \
  --remote-debugging-port=9222 \
  --user-data-dir=/tmp/chrome-headless

Note: Ensure no other Chrome instance is already using port 9222.

Connect via Workspace Config

In Canvas: Workspace → Config → MCP Servers → Add browser MCP server.

Or via API:

curl -X PATCH https://your-platform.molecule.ai/workspaces/${WORKSPACE_ID}/config \
  -H "Authorization: Bearer ${WORKSPACE_TOKEN}" \
  -H "Content-Type: application/json" \
  -d '{
    "mcp_servers": {
      "browser": {
        "type": "streamable_http",
        "url": "http://localhost:9223/mcp"
      }
    }
  }'

Replace http://localhost:9223/mcp with your MCP server URL — for example, a Cloudflare Workers-deployed CDP bridge, or the Chrome DevTools MCP bridge from the Chrome DevTools MCP blog post.

Available MCP Tools

Agents access these tools the same way as any other MCP tool — typed, session-aware, and registered at the workspace level.

Troubleshooting

Port 9222 in use: Find and kill the process with lsof -i :9222 (macOS/Linux) or netstat -ano | findstr :9222 (Windows).

Chrome closes immediately: Run with --user-data-dir=/tmp/chrome-debug to isolate the debugging session from your normal browser profile.

WebSocket connection refused: Ensure the MCP server URL is reachable from your Molecule AI deployment.

For full browser automation examples, see the Chrome DevTools MCP blog post.