Skills

The npm package ships ten skills. They are the main way to work with universal-plugin — each owns one job in the life of a plugin, from scaffolding it through publishing it, and the CLI underneath it is there for scripting and CI, not the primary interface. In Claude Code they are invoked as /universal-plugin:<name>; other runtimes match them against your request.

Authoring a plugin

Five skills cover the life of a plugin. Each is scoped by the thing it touches, which is what keeps them from competing for the same request.

Skill	Owns
init-universal-plugin	what the manifest declares
doctor-universal-plugin	nothing; it only reads
version	the released number
build-plugin	the derived manifests, written
remove-plugin	the artifacts, deleted

Exactly one of them writes the canonical plugin.json. That is init-universal-plugin.

Distribution

Skill	Use it to
marketplace	generate the catalogs that let users install from this repository, and write the README install section
migrate-plugin	move a repository-root plugin into the npm package that ships it
publish-plugin	list a packaged plugin in the shared marketplace repository
upgrade-plugin	bump the pinned universal-plugin@<version> a project calls
adopt-upx	rewrite npx pins in your skills to the upx runner

upgrade-plugin moves the version your project calls. version moves the version your plugin publishes. They are different numbers.

Bundled launchers

init-universal-plugin, doctor-universal-plugin, version, build-plugin, and marketplace each ship a launcher in their own scripts/ directory. The launcher imports the CLI that shipped beside it, so a scaffold or a diagnosis needs no network fetch and cannot resolve a different version than the one you installed.

node scripts/doctor.mjs

Every skill body keeps a pinned npx fallback for the case where the path cannot be resolved. See Running a CLI your own plugin ships for the four requirements that make the pattern work.

Why four skills and not one

The authoring four started as a single gateway skill with a route table. No one name covered create, adopt, update, inspect, version, and delete, and one description that has to match all six matches each of them weakly.

The rule that replaced it: a new verb earns a route on the skill whose object it shares, and a skill of its own only when its object differs. Competing writers on one object are what fragments a surface, not the number of skills. ADR-0009 records the decision.