# Gmc

> Use the `gmc` CLI for explicit gmc requests: generate commit messages, create or remove worktrees, prune merged worktrees, discover or sync shared resources, or run other `gmc wt` subcommands. Triggers mainly when the user invokes `/gmc` or mentions `gmc wt add`, `gmc wt prune`, `gmc wt share`, `gmc wt sync`, `gmc tag`, or asks to use gmc for commit or worktree automation. Do not use for generic git or generic worktree requests unless the user specifically wants `gmc`.

- Skill: `samzong/gmc` (Agent Skill)
- Install (CLI): `npx skillmds@latest add samzong/gmc`
- Raw SKILL.md: https://api.skillmd.com/api/skills/samzong/gmc/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: samzong (https://skillmd.com/u/samzong)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/samzong/gmc

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IRON LAW: ALL WORKTREE OPERATIONS MUST USE `gmc wt <subcommand>`. NEVER INVENT `gmc add`, `gmc rm`, `gmc prune`, `gmc clone`, OR OTHER TOP-LEVEL WORKTREE COMMANDS.

# gmc

Use `$ARGUMENTS` and the user's words to route into exactly one mode.

Copy this checklist and check off items as you complete them:

- [ ] Step 0: Parse intent [BLOCKING]
  - [ ] Classify the request as `commit`, `wt add`, `wt prune`, `wt share`, `wt sync`, `wt rm`, `wt ls`, `wt dup`, `wt pr-review`, or `tag`
  - [ ] If the intent is unclear, ask one focused question before running commands
- [ ] Step 1: Validate context [BLOCKING]
  - [ ] Confirm `gmc` exists
  - [ ] Confirm the current directory is a git repo when the command needs repo context
  - [ ] If the action depends on GitHub state, confirm `gh` works first
- [ ] Step 2: Preview plan [REQUIRED]
  - [ ] Show the exact command you plan to run
  - [ ] For destructive or bulk actions, prefer `--dry-run` first
- [ ] Step 3: Execute exactly one workflow
  - [ ] `commit`
  - [ ] `wt add`
  - [ ] `wt prune`
  - [ ] `wt share`
  - [ ] other `gmc wt` subcommand or `tag`
- [ ] Step 4: Report result
  - [ ] State the exact command run
  - [ ] Report the created path, cleaned worktrees, synced resources, or generated message
  - [ ] State what was not run

## Routing

- `commit` uses top-level `gmc`
- Any worktree action uses `gmc wt <subcommand>`
- If the user says `gmc add`, translate it to `gmc wt add` and say so
- If the user wants generic git help without `gmc`, do not use this skill

## Common commands

- `gmc`
- `gmc -y`
- `gmc -a -y`
- `gmc -a -y -p "context"`
- `gmc --dry-run`
- `gmc wt add <name>`
- `gmc wt add <name> --sync`
- `gmc wt add <name> -b <branch>`
- `gmc wt ls`
- `gmc wt rm <name>`
- `gmc wt rm -D <name>`
- `gmc wt prune`
- `gmc wt sync`
- `gmc wt share ls`
- `gmc wt share add <path> --strategy copy`
- `gmc wt share add <path> --strategy link`
- `gmc wt share sync`
- `gmc tag`

## Workflow: commit mode

- Use top-level `gmc`, not `gmc wt`
- Default to interactive `gmc` unless the user explicitly wants automation
- Ask before `gmc -a -y` because it stages all files and auto-confirms
- Use `gmc --dry-run` when the user wants a suggested message without committing

## Workflow: create worktree

- Use `gmc wt add <name>`
- Use `-b <branch>` only if the user provided a base branch or asked for one
- Use `--sync` only when the user wants the latest base first
- After creation, report the worktree path

## Workflow: prune merged worktrees

- Run `gmc wt prune --dry-run` first to preview
- Use `gmc wt prune --pr-aware` to check PR state before pruning
- Ask before actual removal
- Use `--force` only with explicit user approval

## Workflow: shared resources

- For discovery, run `gmc wt share discover --dry-run`
- Use `gmc wt share discover --auto` only with explicit approval
- For manual control, use `gmc wt share add`, `gmc wt share ls`, `gmc wt share rm`, or `gmc wt share sync`
- Prefer `copy` for env files or local config
- Prefer `link` for large identical directories such as `node_modules` or `.venv`

## Confirmation gates

- Ask before `gmc -a -y`
- Ask before `gmc wt rm -D <name>`
- Ask before any non-dry-run prune
- Ask before `gmc wt share discover --auto`
- Ask before `--force`

## Do not

- Do not run `gmc add`, `gmc rm`, `gmc prune`, `gmc clone`, or `gmc share`
- Do not skip dry-run for cleanup when a preview exists
- Do not use `--auto`, `-a -y`, `-D`, or `--force` without explicit user approval
- Do not guess worktree paths, base branches, or GitHub state
- Do not mix commit mode and worktree mode in the same command