Package skill as a Claude Code plugin

[mrrobertkent]

Packages the skill as a Claude Code plugin, so people can install it per project through the native /plugin workflow instead of copying the folder in by hand.

/plugin marketplace add robonuggets/gauntlet-loop
/plugin install gauntlet-loop@gauntlet-loop

They pick a scope on install — user for every project, project to commit it so a team gets it, local to keep it off tracked files — and updates arrive with /plugin update. The repo hosts its own marketplace, so there is no second repo to keep in sync.

Try it without installing anything

git clone -b feat/plugin-marketplace https://github.com/mrrobertkent/gauntlet-loop
claude --plugin-dir ./gauntlet-loop

That loads the plugin for one session and touches no config. /gauntlet-loop:gauntlet-loop works immediately.

What changed

.claude-plugin/plugin.json, .claude-plugin/marketplace.json	new — makes the repo an installable, self-hosting marketplace
.claude/skills/gauntlet-loop/ → skills/gauntlet-loop/	moved — Claude Code resolves a plugin's skills at <plugin-root>/skills/
/gauntlet-loop → /gauntlet-loop:gauntlet-loop	plugin skills are namespaced
skills/migrate/, migrate/, bin/	new — the migration tool below
CHANGELOG.md, README.md	version history, and a quick start covering both install paths

Your prompt is untouched. Git records SKILL.md as a rename; the only edits are three frontmatter lines — the namespaced trigger string, argument-hint: [goal], and license: CC-BY-4.0. The body is byte-identical. The credit to Matt Shumer is intact in both the README and the skill.

Natural-language triggers — "gauntlet this", "gauntlet loop" — are unaffected.

Anyone who already copied the skill in

Their copy keeps working but will never update, and it does not get replaced by the plugin — Claude Code namespaces the plugin skill rather than overriding the loose one, so installing on top leaves /gauntlet-loop and /gauntlet-loop:gauntlet-loop both live.

/gauntlet-loop:migrate cleans that up. It reads Claude Code's own project index, so it probes known paths rather than scanning the filesystem:

Found 3 hand-copied install(s) of `gauntlet-loop`:

  [ok]   ~/acme-web
         ~/acme-web/.claude/skills/gauntlet-loop (enabled)
  [ok]   ~/internal-docs
         ~/internal-docs/.claude/skills/gauntlet-loop (disabled)
  [skip] ~/side-project
         ~/side-project/.claude/skills/gauntlet-loop (enabled)
         contains files we did not ship: NOTES.md

1 skipped. Those directories were modified locally, so they are left alone.

This was a dry run. Nothing has changed.
Re-run with --write to replace the 2 recognised install(s) with the plugin.

Each one is replaced at the same scope it occupied, and internal-docs stays disabled afterwards. Beyond the dry-run default, three things it will not do:

• It installs and verifies the plugin before removing anything, so a failed install leaves the existing skill working rather than deleting it and stranding the user.
• It never touches a directory holding a file this project does not ship. It reports it, as above.
• It shells out to the claude CLI for every change rather than editing settings files itself.

Source is in migrate/ — one Rust file, one dependency, no runtime needed on the user's machine.

One question

The repo is CC BY 4.0, a content licence. Good fit for a Markdown skill, awkward now that there is Rust in the tree, which I labelled CC-BY-4.0 to match rather than pick for you. If you would rather the tooling carry MIT or Apache-2.0, say which and I will change it.