Devcontainer Browser

An isolated Chromium browser designed for AI agents running inside development containers.

When started, this project launches Chromium inside a dedicated Docker container. The browser exposes its Chrome DevTools Protocol (CDP) endpoint through:

0.0.0.0:9223

AI agents can connect to this browser from another devcontainer and control it using tools such as Playwright.

Quick Start

Run:

curl https://raw.githubusercontent.com/calcite/devcontainer_browser/refs/heads/master/dev_browser.sh | sh

This starts the Chromium container and exposes its debugging endpoint on port 9223.

Devcontainer Configuration

To make the Docker host accessible from your devcontainer, add the following entry to extra_hosts:

extra_hosts:
  - "host.docker.internal:host-gateway"

For example, in docker-compose.yml:

services:
  devcontainer:
    extra_hosts:
      - "host.docker.internal:host-gateway"

The browser is then available from inside the devcontainer at:

http://host.docker.internal:9223

Using It with an AI Agent

Once the browser is running, instruct your AI agent to connect to the existing Chromium instance using Playwright over CDP.

For example:

const { chromium } = require("playwright");

const browser = await chromium.connectOverCDP(
  "http://host.docker.internal:9223"
);

This keeps the browser isolated in its own container while allowing agents running in development containers to interact with a real Chromium instance.