claude-cmux-skill
Orchestrate independent Claude Code sessions in cmux — split panes, monitor agents, automate browsers, coordinate parallel work
Running multiple AI agents but can't see what they're doing?
That's what happens when your terminal wasn't built for agent orchestration.
Installation • Usage • The Problem • How It Works • Examples
This plugin teaches Claude Code how to use cmux — a native macOS terminal built for AI coding agents. Use /cmux to spawn parallel Claude Code sessions in split panes, monitor agent output, automate browsers, manage notifications, and coordinate multi-agent workflows.
Installation
| Platform | How to install |
|---|
| Claude Code | claude plugin marketplace add ph3on1x/claude-cmux-skill
claude plugin install claude-cmux-skill |
[!NOTE]
Requires cmux (macOS 14.0+) and Claude Code CLI. Use /cmux to invoke the skill inside a cmux terminal.
When to Use What
| You're thinking... | Use | What happens |
|---|
| "I need three agents working in parallel" | /cmux Spin up 3 agents to research X, Y, Z | Creates split panes, launches independent Claude Code sessions, monitors output via read-screen, coordinates with sync tokens |
| "What's my other agent doing?" | /cmux Check agent progress in surface:5 | Reads terminal output from any surface without switching to it, reports status |
| "I need to test this in a browser" | /cmux Open browser and test the login flow | Opens browser surface, snapshots for element refs, interacts via click/fill — no CSS selectors |
| "Notify me when the build finishes" | /cmux Notify me when the build finishes | Uses cmux notify (in-app) or osascript (system-level) based on context |
| "I need agents to share data" | /cmux Share API findings with the test agent | Stores results in named buffers, signals completion with wait-for tokens |
The Problem
AI coding agents are powerful individually. But when you need multiple agents working in parallel:
- No visibility — you can't see what other agents are doing without switching panes manually
- No coordination — agents can't signal completion or share results with each other
- No orchestration — splitting work across panes, monitoring progress, and collecting results requires manual effort
How It Works
Invoke with /cmux inside a cmux terminal. The skill uses progressive disclosure — core concepts load when /cmux is invoked, while detailed references load only when Claude needs them.
claude-cmux-skill/
├── .claude-plugin/
│ ├── plugin.json # Plugin metadata
│ └── marketplace.json # Marketplace catalog
├── hooks/
│ └── hooks.json # Lifecycle hooks (SessionStart, Stop, Notification)
└── skills/
└── cmux/
├── SKILL.md # /cmux skill
└── references/
├── orchestration.md # Multi-agent patterns
├── browser-automation.md # Full browser API
├── notifications.md # Notification systems
└── complete-cli.md # Complete CLI catalog
Key Capabilities
