Real Chrome DevTools Protocol With uv

This project contains one realistic browser IPC example: a Python client that talks to a real Chrome or Microsoft Edge process through the Chrome DevTools Protocol (CDP). It does not simulate Mojo or fake browser state.

The client launches or attaches to a browser, creates a page target, navigates it, evaluates JavaScript in the renderer, observes network events, and writes a screenshot captured by the browser.

Run

uv sync
uv run python cdp_example.py

The default run writes cdp-screenshot.png, which is ignored by git.

If Chrome or Edge is not in a standard location:

uv run python cdp_example.py --browser-executable "C:\\Path\\To\\chrome.exe"

To attach to an already-running browser:

chrome --remote-debugging-port=9222 --user-data-dir=%TEMP%\cdp-profile
curl http://127.0.0.1:9222/json/version
uv run python cdp_example.py --browser-ws-url <webSocketDebuggerUrl from /json/version>

Files

File	Purpose
cdp_example.py	Real CDP client.
pyproject.toml	uv project metadata and Python dependencies.
docs/sample.md	Sample commands and output.
docs/mini_cdp.md	Minimal CDP protocol notes for this project.

Requirements

• uv
• Python 3.13 or newer, managed by uv
• Chrome or Microsoft Edge

Why CDP, Not Mojo

True Mojo IPC is Chromium-internal. A real Mojo service needs Chromium's C++ generated bindings, GN/Ninja build integration, platform handle passing, task runners, sandbox-aware process setup, and .mojom code generation.

For a standalone tool that controls or inspects a real browser, CDP is the realistic external protocol.

Resources

• Chrome DevTools Protocol
• Mojo Documentation