cmux-customization Skill

1---2name: cmux-customization3description: "Customize cmux for an end user. Use when changing cmux.json actions, custom commands, workspace layouts, plus-button behavior, surface tab bar buttons, Command Palette entries, Dock controls, sidebar and app settings, shortcuts, notifications, browser routing, examples-library presets, or Ghostty-backed terminal preferences."4---5 6# cmux Customization7 8Keep the user's config intact, prefer schema-backed edits, and validate before reporting completion.9 10## Choose the right surface11 12| Want to change | Edit |13|---|---|14| App preferences (appearance, sidebar, notifications, browser routing, automation, shortcuts, new-workspace placement) | `~/.config/cmux/cmux.json` via the `cmux-settings` helper |15| Custom actions, workspace layouts/commands, tab bar buttons, plus-button behavior, Command Palette entries, notification hooks | `~/.config/cmux/cmux.json` globally or `.cmux/cmux.json` in the project |16| Dock controls (right-sidebar terminals: logs, test watchers, git TUIs, dev servers, queues, `cmux feed tui --opentui`) | `.cmux/dock.json` or `~/.config/cmux/dock.json`; `cmux docs dock` when available |17| Terminal rendering and terminal keybindings (fonts, themes, cursor style, copy-on-select, shell integration) | Ghostty config, usually `~/.config/ghostty/config` |18| Workspace names, descriptions, colors, read state, sidebar metadata | cmux CLI, see [../cmux-workspace/SKILL.md](../cmux-workspace/SKILL.md) |19| Feed event sources | `cmux hooks setup` |20 21Project-local `.cmux/cmux.json` and `.cmux/dock.json` let worktree, SSH, review, dev, CI, and docs patterns travel with the repo; project actions and commands override global entries with the same ID or name. Global app preferences do not belong there.22 23If a request can be handled by Ghostty config, say so and use Ghostty config instead of inventing cmux UI settings.24 25Key surfaces in `cmux.json`: `actions` (reusable, can appear in Cmd+Shift+P, surface tab bars, shortcuts, and the plus-button right-click menu), `ui.newWorkspace.action` (replaces the plus-button click) and `ui.newWorkspace.contextMenu` (right-click menu; `ui.newWorkspace.rightClick` is an accepted alias but new examples use `contextMenu`), `ui.surfaceTabBar.buttons` (replaces default tab bar buttons; include built-ins like `cmux.newTerminal`, `cmux.newBrowser`, `cmux.splitRight`, `cmux.splitDown` only when they should stay visible), and `commands` (workspace definitions with split layouts).26 27## Workflow28 291. Inspect existing config.30 31   ```bash32   test -f ~/.config/cmux/cmux.json && sed -n '1,220p' ~/.config/cmux/cmux.json33   test -f .cmux/cmux.json && sed -n '1,220p' .cmux/cmux.json34   ```35 362. Pick global or project-local scope. Default to project-local for repo-specific commands, global for app preferences. Ask only when the choice changes behavior meaningfully.373. Back up the target file when it already exists (applicable path only, no backup for a missing file).38 39   ```bash40   stamp="$(date +%Y%m%d-%H%M%S)"41   test -f ~/.config/cmux/cmux.json && cp -p ~/.config/cmux/cmux.json ~/.config/cmux/cmux.json."$stamp".bak42   test -f .cmux/cmux.json && cp -p .cmux/cmux.json .cmux/cmux.json."$stamp".bak43   ```44 454. For app settings and cmux-owned shortcuts, use the settings helper (`~/.codex/skills/...` if the user installed with `skills.sh`).46 47   ```bash48   ~/.agents/skills/cmux-settings/scripts/cmux-settings list-supported49   ~/.agents/skills/cmux-settings/scripts/cmux-settings set browser.openTerminalLinksInCmuxBrowser true50   ~/.agents/skills/cmux-settings/scripts/cmux-settings validate51   ```52 535. For actions, UI wiring, workspace layouts, notification hooks, and Dock controls, edit the JSONC by hand and preserve unrelated sections (`vault`, `rightSidebar`, `commands`, `actions`, `ui`, `notifications`).546. `cmux reload-config`.557. Verify the configured entrypoint exists: read back the shortcut binding, or confirm the action ID and where it should appear.56 57## Example: Command Palette action58 59Appears in Cmd+Shift+P unless `palette` is false.60 61```json62{63  "actions": {64    "codex-new-tab": {65      "type": "agent",66      "agent": "codex",67      "title": "Codex",68      "subtitle": "Start Codex in this workspace",69      "target": "newTabInCurrentPane",70      "palette": true71    }72  }73}74```75 76For worktree agents, full-stack dev layouts, SSH devboxes, PR review workspaces, docs workspaces, tab bar buttons, and CI watch Dock controls, read [references/examples.md](references/examples.md). Load it when the user asks for examples, presets, templates, starter configs, or a known workflow shape.77 78## Validation79 80- App settings: `cmux-settings validate`.81- Keep valid JSONC, no duplicate keys.82- Parse `.cmux/dock.json` or `~/.config/cmux/dock.json` with a JSON parser before reporting completion.83- `cmux reload-config` when the CLI is available.84- Confirm the exact user-facing result: action title, shortcut, plus-button behavior, context-menu entry, or tab bar placement.85 86## Rules87 88- Do not overwrite a whole top-level config section unless you own the full section.89- Do not store secrets in actions, commands, or prompts. Use environment variables or the user's secret manager.90- Do not use sleeps or timing workarounds in generated commands.91- Do not add a cmux setting for behavior Ghostty already owns.92- Keep labels short enough for menus, buttons, and the Command Palette.93