| name | agent-browser |
| description | Use when you need to screenshot or drive a dev server and the shared Chrome is unavailable or contended — e.g. parallel Conductor workspaces: headless per-workspace browser via npx agent-browser. |
agent-browser — headless per-workspace browser
Browser automation CLI from Vercel Labs. Native Rust binary driving Chrome/Chromium over
CDP — no Playwright, no shared Chrome window. Each --session gets its own browser
instance, cookies, and history, so parallel Conductor workspaces never fight over tabs.
Needs node/npx. Run every command through npx agent-browser ... (or agent-browser if
installed globally with npm i -g agent-browser). First use on a machine may need
npx agent-browser install to download Chrome for Testing; existing Chrome, Brave,
Playwright, and Puppeteer installs are detected automatically.
Isolate the workspace first
SESSION="$(npx agent-browser session id --scope worktree --prefix dev-loop)"
The browser persists via a background daemon, so chaining commands with && is safe.
The ui-iterate loop
Screenshot the affected route at all three widths, then critique the images:
URL="http://localhost:${CONDUCTOR_PORT:-3000}/route-you-changed"
npx agent-browser --session "$SESSION" open "$URL"
npx agent-browser --session "$SESSION" --load networkidle
npx agent-browser --session viewport 375 812
npx agent-browser --session screenshot /tmp/ui-375.png
npx agent-browser --session viewport 768 1024
npx agent-browser --session screenshot /tmp/ui-768.png
npx agent-browser --session viewport 1440 900
npx agent-browser --session screenshot /tmp/ui-1440.png
