cmux-keyboard-shortcuts

SKILL.md

cmux-keyboard-shortcuts

Use this skill to turn a user's workflow preferences into cmux shortcut bindings in ~/.config/cmux/cmux.json. It should guide the user, propose compact templates, apply selected changes, and confirm the config parses with recognized keys.

Prerequisites

Work from a cmux checkout or worktree root when possible.

Use skills/cmux-settings/scripts/cmux-settings for every read/write. It reads JSONC, writes atomically, and validates JSON plus recognized settings keys.

For action IDs, read skills/cmux-settings/references/shortcut-actions.md.

For current defaults, read web/data/cmux-shortcuts.ts or Sources/KeyboardShortcutSettings.swift.

find_cmux_settings() {
  local root
  root="$(git -C "$(pwd)" rev-parse --show-toplevel 2>/dev/null || pwd)"
  for candidate in \
    "$root/skills/cmux-settings/scripts/cmux-settings" \
    "${CODEX_HOME:-$HOME/.codex}/skills/cmux-settings/scripts/cmux-settings" \
    "$HOME/.agents/skills/cmux-settings/scripts/cmux-settings"; do
    if [[ -x "$candidate" ]]; then
      printf '%s\n' "$candidate"
      return 0
    fi
  done
  return 1
}

if [[ -z "${CMUX_SETTINGS:-}" ]]; then
  CMUX_SETTINGS="$(find_cmux_settings)" || {
    echo "cmux-settings helper not found; run from a cmux checkout or install cmux-settings" >&2
    exit 1
  }
fi

Shortcut Model

Setting path: shortcuts.bindings.<actionId>.

Single stroke: "cmd+b".

Chord: ["ctrl+b","c"]. The first stroke needs a modifier unless the key is Space. The second stroke can be bare.

Unbind: prefer null for explicit unbinds. "", "none", "clear", "unbound", and "disabled" are accepted aliases, but null is the clearest JSON value and matches the templates below.

selectSurfaceByNumber and selectWorkspaceByNumber must use a digit from 1 to 9. cmd+1 means the full cmd+1 through cmd+9 family.

showHideAllWindows and globalSearch are system-wide shortcuts. They cannot be chords, require modifiers, and may be rejected by macOS if reserved.

showHideAllWindows also requires Settings > Global Hotkey > Enable System-Wide Hotkey. The binding can validate in cmux.json while the feature is disabled, so warn the user to enable that setting before reporting the shortcut as usable.

unset deletes a cmux.json override. It does not clear shortcut changes saved through the Settings UI/UserDefaults. If the user asks for true built-in defaults, tell them to use Settings > Keyboard Shortcuts > Reset Default Shortcuts after clearing file-managed overrides, then verify in the app. For showHideAllWindows, use Settings > Global Hotkey to restore the shortcut to ctrl+opt+cmd+. because Keyboard Shortcuts > Reset Default Shortcuts intentionally skips the global hotkey.

Saving cmux.json live reloads. Do not tell the user to restart cmux.

Workflow

Classify the request:

One-off rebind or unbind: map the phrase to an action ID, apply it, validate, and report the previous and new binding.

Audit-only request: inspect current bindings, validate, and summarize overrides/unbound shortcuts without writing.

Reset request: clarify whether the user means file-managed overrides or true built-in defaults. For file-managed resets, use unset for named actions. For true built-in defaults, remove file overrides and direct the user to Settings > Keyboard Shortcuts > Reset Default Shortcuts; do not report built-in defaults restored from cmux-settings alone. If showHideAllWindows is included, also direct them to Settings > Global Hotkey to restore ctrl+opt+cmd+. and the enable toggle.

Broad customization request: propose 3 to 5 templates from "Preset Templates" and ask the user to choose.

Named style such as tmux, Vim, iTerm, browser, or agent triage: select the closest template, show the changed actions and likely collisions, and ask before a bulk apply unless the user explicitly said to apply it.

Inspect existing config:

"$CMUX_SETTINGS" path
"$CMUX_SETTINGS" get shortcuts.bindings 2>/dev/null || printf '{}\n'
"$CMUX_SETTINGS" validate

Before applying a template, snapshot prior values for every action you will change. A path that is absent must revert with unset; a path with an existing custom value must revert with set <same-json-value>.

"$CMUX_SETTINGS" get shortcuts.bindings.focusLeft 2>/dev/null || printf '<absent>\n'

Apply only the chosen action paths:

"$CMUX_SETTINGS" set shortcuts.bindings.newSurface '["ctrl+b","c"]'
"$CMUX_SETTINGS" set shortcuts.bindings.focusLeft cmd+opt+h
"$CMUX_SETTINGS" set shortcuts.bindings.sendFeedback null
"$CMUX_SETTINGS" validate

Verify readback for changed actions:

"$CMUX_SETTINGS" get shortcuts.bindings.newSurface

Finish with the template name, changed actions, and exact revert commands from the snapshot. Use unset only for actions that were absent before the template; use set to restore previous custom bindings.

Preset Templates

Use these as proposal templates. Apply them action by action, not by overwriting the whole shortcuts.bindings object.

Tmux Prefix

For users who want one terminal-style shortcut namespace and accept that ctrl+b starts a cmux chord instead of going directly to the shell.

"$CMUX_SETTINGS" set shortcuts.bindings.newSurface '["ctrl+b","c"]'
"$CMUX_SETTINGS" set shortcuts.bindings.closeTab '["ctrl+b","x"]'
"$CMUX_SETTINGS" set shortcuts.bindings.nextSurface '["ctrl+b","n"]'
"$CMUX_SETTINGS" set shortcuts.bindings.prevSurface '["ctrl+b","p"]'
"$CMUX_SETTINGS" set shortcuts.bindings.selectSurfaceByNumber '["ctrl+b","1"]'
"$CMUX_SETTINGS" set shortcuts.bindings.splitRight '["ctrl+b","v"]'
"$CMUX_SETTINGS" set shortcuts.bindings.splitDown '["ctrl+b","s"]'
"$CMUX_SETTINGS" set shortcuts.bindings.focusLeft '["ctrl+b","h"]'
"$CMUX_SETTINGS" set shortcuts.bindings.focusDown '["ctrl+b","j"]'
"$CMUX_SETTINGS" set shortcuts.bindings.focusUp '["ctrl+b","k"]'
"$CMUX_SETTINGS" set shortcuts.bindings.focusRight '["ctrl+b","l"]'
"$CMUX_SETTINGS" set shortcuts.bindings.toggleSplitZoom '["ctrl+b","z"]'
"$CMUX_SETTINGS" set shortcuts.bindings.toggleTerminalCopyMode '["ctrl+b","["]'
"$CMUX_SETTINGS" set shortcuts.bindings.equalizeSplits '["ctrl+b","="]'

macOS Terminal/iTerm Restore

For users who want surface, split, and tab behavior to feel like common macOS terminals again. These actions already match cmux built-in defaults when no Settings UI override exists, so unset file overrides instead of writing default values.

"$CMUX_SETTINGS" unset shortcuts.bindings.newSurface
"$CMUX_SETTINGS" unset shortcuts.bindings.closeTab
"$CMUX_SETTINGS" unset shortcuts.bindings.nextSurface
"$CMUX_SETTINGS" unset shortcuts.bindings.prevSurface
"$CMUX_SETTINGS" unset shortcuts.bindings.selectSurfaceByNumber
"$CMUX_SETTINGS" unset shortcuts.bindings.splitRight
"$CMUX_SETTINGS" unset shortcuts.bindings.splitDown
"$CMUX_SETTINGS" unset shortcuts.bindings.toggleSplitZoom
"$CMUX_SETTINGS" unset shortcuts.bindings.toggleTerminalCopyMode
"$CMUX_SETTINGS" unset shortcuts.bindings.renameTab

Vim Pane Navigation

For users who want fast pane movement without a prefix and do not want to depend on arrow keys.

"$CMUX_SETTINGS" set shortcuts.bindings.focusLeft cmd+opt+h
"$CMUX_SETTINGS" set shortcuts.bindings.focusDown cmd+opt+j
"$CMUX_SETTINGS" set shortcuts.bindings.focusUp cmd+opt+k
"$CMUX_SETTINGS" set shortcuts.bindings.focusRight cmd+opt+l
"$CMUX_SETTINGS" set shortcuts.bindings.splitRight cmd+opt+v
"$CMUX_SETTINGS" set shortcuts.bindings.splitDown cmd+opt+s
"$CMUX_SETTINGS" set shortcuts.bindings.toggleSplitZoom cmd+opt+z
"$CMUX_SETTINGS" set shortcuts.bindings.equalizeSplits cmd+opt+=

Agent Triage

For users who live in notifications and want unread handling on one key family. This keeps toggle unread on cmd+opt+u so it can be combined with Vim Pane Navigation without colliding with cmd+opt+j.

"$CMUX_SETTINGS" set shortcuts.bindings.showNotifications cmd+u
"$CMUX_SETTINGS" set shortcuts.bindings.jumpToUnread cmd+j
"$CMUX_SETTINGS" set shortcuts.bindings.markOldestUnreadAndJumpNext cmd+shift+j
"$CMUX_SETTINGS" set shortcuts.bindings.toggleUnread cmd+opt+u
"$CMUX_SETTINGS" set shortcuts.bindings.triggerFlash cmd+shift+h
"$CMUX_SETTINGS" set shortcuts.bindings.focusRightSidebar cmd+shift+e

Workspace And Surface Lanes

For users who want workspaces and surfaces on distinct number and bracket lanes.

"$CMUX_SETTINGS" set shortcuts.bindings.selectWorkspaceByNumber cmd+1
"$CMUX_SETTINGS" set shortcuts.bindings.selectSurfaceByNumber cmd+opt+1
"$CMUX_SETTINGS" set shortcuts.bindings.nextSidebarTab 'cmd+opt+]'
"$CMUX_SETTINGS" set shortcuts.bindings.prevSidebarTab 'cmd+opt+['
"$CMUX_SETTINGS" set shortcuts.bindings.nextSurface 'cmd+shift+]'
"$CMUX_SETTINGS" set shortcuts.bindings.prevSurface 'cmd+shift+['

Browser Defaults Restore

For users who changed too much and want embedded-browser behavior to match common macOS browser shortcuts again. Use unset to clear file overrides so future cmux defaults still apply when no Settings UI override exists.

"$CMUX_SETTINGS" unset shortcuts.bindings.openBrowser
"$CMUX_SETTINGS" unset shortcuts.bindings.focusBrowserAddressBar
"$CMUX_SETTINGS" unset shortcuts.bindings.browserBack
"$CMUX_SETTINGS" unset shortcuts.bindings.browserForward
"$CMUX_SETTINGS" unset shortcuts.bindings.browserReload
"$CMUX_SETTINGS" unset shortcuts.bindings.browserZoomIn
"$CMUX_SETTINGS" unset shortcuts.bindings.browserZoomOut
"$CMUX_SETTINGS" unset shortcuts.bindings.browserZoomReset
"$CMUX_SETTINGS" unset shortcuts.bindings.toggleBrowserDeveloperTools
"$CMUX_SETTINGS" unset shortcuts.bindings.showBrowserJavaScriptConsole
"$CMUX_SETTINGS" unset shortcuts.bindings.find
"$CMUX_SETTINGS" unset shortcuts.bindings.findNext
"$CMUX_SETTINGS" unset shortcuts.bindings.findPrevious

Terminal-First Cleanup

For users who want fewer app-level shortcuts. Prefer unbinding only the actions they name, but this is a reasonable starting proposal.

"$CMUX_SETTINGS" set shortcuts.bindings.renameTab null
"$CMUX_SETTINGS" set shortcuts.bindings.renameWorkspace null
"$CMUX_SETTINGS" set shortcuts.bindings.editWorkspaceDescription null
"$CMUX_SETTINGS" set shortcuts.bindings.triggerFlash null
"$CMUX_SETTINGS" set shortcuts.bindings.sendFeedback null

Rules

Do not edit ~/.config/cmux/settings.json unless the user explicitly asks. It is legacy fallback config.

Do not overwrite all of shortcuts.bindings unless the user explicitly wants a full replacement.

Do not invent action IDs. Validate against the schema or shortcut-actions.md.

Do not apply a broad template without showing the changed actions first unless the user explicitly said to apply that named template.

Do not promise conflict detection from cmux-settings validate; it validates JSON and supported keys, not shortcut syntax, macOS reservation, or every focus-context conflict.

Before assigning cmd+[ or cmd+] to application-scoped actions, warn that they collide with common browser Back/Forward behavior unless the browser actions are also changed or unbound.

Prefer unset to clear file-managed overrides for individual actions. Do not call this a built-in default reset unless Settings UI/UserDefaults values have also been reset:

"$CMUX_SETTINGS" unset shortcuts.bindings.focusLeft
"$CMUX_SETTINGS" validate