cmux-browser skill

A Claude Code skill for driving the cmux browser command group — browser automation straight from your terminal agent.

With this skill, Claude can navigate pages, manipulate the DOM, fill and submit forms, capture screenshots, run JavaScript, emulate devices, intercept network requests, and manage login sessions through the cmux browser CLI.

Targets cmux 0.64.14+. The skill always tells Claude to confirm the installed CLI's signatures with cmux browser (no args) before using newer commands, so it degrades gracefully across versions.

Requirements

• Claude Code
• The cmux CLI available on your PATH (cmux --version)

Install

Option A — as a plugin (recommended)

/plugin marketplace add junho85/cmux-browser-skill
/plugin install cmux-browser

This installs the skill and lets Claude Code keep it updated.

Option B — manual copy

git clone https://github.com/junho85/cmux-browser-skill.git
cp -r cmux-browser-skill/plugins/cmux-browser/skills/cmux-browser \
      ~/.claude/skills/cmux-browser

What it covers

• Surface model — how cmux manages browser instances and why you should reuse one surface ID instead of re-opening.
• Core workflow — open / wait / snapshot / fill / click / debug / save state.
• Inspection — snapshot, get, is, find, screenshot, highlight.
• State — cookies, local/session storage, state save|load, profiles, and importing existing browser logins (import --from chrome ...).
• Advanced (0.64.14) — device emulation (viewport/geo/offline), request control (network route), and recording (trace, screencast).

See SKILL.md for the guide and api_reference.md for the full command reference.

License

MIT