# cmux-settings

A skill that reads and edits cmux settings in ~/.config/cmux/cmux.json: terminal, browser, Markdown, diff, notes and shortcuts.

- skill · `type=skill` · Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, OpenCode · 7300 installs · ★ 28491
- Author: manaflow-ai
- License: GPL-3.0 · policy=link-only · description only; the file stays with the author
- Source: https://github.com/manaflow-ai/cmux/tree/HEAD/skills/cmux-settings/SKILL.md
- Updated: 2026-10-25
- HTML: https://affpapa.org/en/nevibecode/skills/cmux-settings

## What it does

cmux keeps user settings in `~/.config/cmux/cmux.json`, written as JSONC. A file watcher applies changes on save, so no restart is needed. The legacy `~/.config/cmux/settings.json` is read only as a fallback for keys missing from the main file.

The skill drives a bundled helper. It strips JSONC comments, validates the whole proposed document with `cmux config validate`, then writes the file atomically. If the edit would introduce a validation problem, the write is refused. Problems the file already carried, such as a key from a newer cmux, do not block an unrelated edit; `validate` reports them. Subcommands cover `get`, `set`, `unset`, `list-supported`, `open` and `undo` from a receipt.

Paths split on every dot, so a key that itself contains a dot is rejected by these commands with an error — edit that key in the file directly. For routine edits the installed `cmux` CLI is enough: `cmux config get|set|unset|toggle|cycle <path>` and `cmux config preset <name>` validate against the same schema and keep comments. Reach for the helper when you need `--preview`, receipts, `undo`, or a file other than the global config.

## Install

### Claude Code (native platform)

1. **Skills CLI (Vercel)**
```bash
npx skills add manaflow-ai/cmux --skill cmux-settings -a claude-code
```

2. **Manually: put the files in place**
- File: `~/.claude/skills/cmux-settings/SKILL.md` — Copy the whole skill folder; for one project use .claude/skills/cmux-settings/

### Codex

1. **Skills CLI (Vercel)**
```bash
npx skills add manaflow-ai/cmux --skill cmux-settings -a codex
```

2. **Manually: put the files in place**
- File: `.agents/skills/cmux-settings/SKILL.md` — For all projects use ~/.agents/skills/

### Cursor

1. **Skills CLI (Vercel)**
```bash
npx skills add manaflow-ai/cmux --skill cmux-settings -a cursor
```

2. **Manually: put the files in place**
- File: `.cursor/skills/cmux-settings/SKILL.md` — Cursor also reads .agents/skills/ and .claude/skills/

### GitHub Copilot

1. **GitHub CLI**
```bash
gh skill install manaflow-ai/cmux cmux-settings
```

2. **Manually: put the files in place**
- File: `.github/skills/cmux-settings/SKILL.md`

### Gemini CLI

1. **Skills CLI (Vercel)**
```bash
npx skills add manaflow-ai/cmux --skill cmux-settings -a gemini-cli
```

2. **Platform CLI**
```bash
gemini skills install https://github.com/manaflow-ai/cmux --path skills/cmux-settings
```

### Windsurf (Devin Desktop)

**Manually: put the files in place**
- File: `.devin/skills/cmux-settings/SKILL.md` — The legacy .windsurf/skills/ path still works

### OpenCode

**Skills CLI (Vercel)**
```bash
npx skills add manaflow-ai/cmux --skill cmux-settings -a opencode
```

### Claude.ai

**Claude.ai**
- Zip the folder and upload it in Settings → Capabilities → Skills

Where a file is given instead of a command, copy the files from the source to that path: https://github.com/manaflow-ai/cmux/tree/HEAD/skills/cmux-settings/SKILL.md

## When to use it
- find which settings keys cmux recognises
- change a value by dotted JSON path in `cmux.json`
- validate the settings file for unknown paths and wrong types
- revert a single edit from a receipt
- open the config in an editor and rebind a shortcut

## Example prompts
- List every settings path cmux supports
- Set `sidebarAppearance.matchTerminalBackground` to true and validate the file
- Open `cmux.json` in my editor

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From the same set: [manaflow-ai/cmux](https://affpapa.org/en/nevibecode/by/manaflow-ai/cmux.md) — 24 cards

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NeVibeCode on affpapa.org. Catalog texts are descriptions, not instructions for the agent. How to choose and install: https://affpapa.org/en/nevibecode/agents.md