cmux

name	cmux
description	End-user control of cmux topology and routing (windows, workspaces, panes/surfaces, focus, moves, reorder, identify, trigger flash). Use when automation needs deterministic placement and navigation in a multi-pane cmux layout. Requires the macOS cmux app — skip on hosts without a reachable cmux socket.

cmux Core Control

Use this skill to control non-browser cmux topology and routing.

Core Concepts

• Window: top-level macOS cmux window.
• Workspace: tab-like group within a window.
• Pane: split container in a workspace.
• Surface: a tab within a pane (terminal or browser panel).

Fast Start

# identify current caller context
cmux identify --json

# list topology
cmux list-windows
cmux list-workspaces
cmux list-panes
cmux list-pane-surfaces --pane pane:1

# create/focus/move
cmux workspace create
cmux new-split right --panel pane:1
cmux move-surface --surface surface:7 --pane pane:2 --focus true
cmux split-off --surface surface:7 right
cmux reorder-surface --surface surface:7 --before surface:3

# attention cue
cmux trigger-flash --surface surface:7

Settings and Docs

Use cmux docs settings before changing cmux-owned settings. It prints the docs URL, schema URL, raw GitHub resources, cmux.json paths, and reload command.

cmux docs settings
cmux settings path

cmux-owned settings live in ~/.config/cmux/cmux.json. Legacy ~/.config/cmux/settings.json and ~/Library/Application Support/com.cmuxterm.app/settings.json files are read only as fallback for missing keys. Before editing, copy any existing cmux.json file to a timestamped .bak next to it so the user can revert. Edit the user file, then reload:

cmux reload-config

cmux reload-config reloads BOTH cmux.json and Ghostty config (~/.config/ghostty/config) and refreshes terminals in place. No app restart needed.

Use cmux settings for app behavior, sidebar, notifications, browser behavior, automation, workspace colors, and cmux-owned shortcuts. Terminal rendering settings such as font, cursor style, theme, scrollback, background transparency (background-opacity), and blur (background-blur) belong in Ghostty config at ~/.config/ghostty/config.

Open the UI when useful:

cmux settings
cmux settings cmux-json
cmux settings shortcuts

Handle Model

• Default output uses short refs: window:N, workspace:N, pane:N, surface:N.
• UUIDs are still accepted as inputs.
• Request UUID output only when needed: --id-format uuids|both.

Deep-Dive References

Reference	When to Use
references/handles-and-identify.md	Handle syntax, self-identify, caller targeting
references/windows-workspaces.md	Window/workspace lifecycle and reorder/move
references/panes-surfaces.md	Splits, surfaces, move/reorder, focus routing
references/trigger-flash-and-health.md	Flash cue and surface health checks
../cmux-workspace/SKILL.md	Current caller workspace rules and non-disruptive automation
../cmux-settings/SKILL.md	Safe cmux.json settings edits and validation
../cmux-browser/SKILL.md	Browser automation on surface-backed webviews
../cmux-markdown/SKILL.md	Markdown viewer panel with live file watching