cmux-terminal-multiplexer

Skill by ara.so — Daily 2026 Skills collection cmux is a terminal multiplexer with a programmable socket API designed for AI coding agents. It provides full Playwright-equivalent browser automation, real-time terminal split management, sidebar status reporting, and agent team coordination — all via a simple CLI. Environment variables set automatically: Handles use short refs: surface:N , pane:N , workspace:N , window:N . Always capture the returned surface_ref : Golden rule: never steal focus. Always use --surface targeting. cmux embeds a full headless Chromium engine with a Playwright-style API. No external Chrome required. Every command targets a browser surface by ref. Capture the surface ref: Instead of CSS selectors, snapshot to get stable element refs ( e1 , e2 , ...): Refs are invalidated after DOM mutations — always re-snapshot after navigation or clicks.