ivar skill

A skill is a folder with a SKILL.md that teaches an agent how to do something in your codebase. ivar installs them, tracks where they came from, and materialises them into each harness's native location — so the same set follows you across harnesses instead of being re-installed per tool.

Where skills come from

Two origins, and the difference matters when two of them share a name.

Repo skills ship inside a repo and keep their origin in their name:

api--openapi-contract
web--openapi-contract

Both repos can ship an openapi-contract skill and neither shadows the other. Without the prefix they land in the same folder, one silently wins, and you find out much later that the agent has been following the wrong one.

Hall skills live in the hall's shared skills directory, mount flat, and apply to the whole session — commit conventions, review checklists, anything that is not about one repo in particular.

Install

ivar skill add https://github.com/acme/skills --path skills/commit-style --ref v2

--path points at a sub-folder when the repo holds more than one skill, and --ref pins to a branch, tag or sha. Skills installed this way are external: ivar remembers the source and can update them.

ivar skill create commit-style   # scaffold an authored skill instead

Update and detach

ivar skill update              # bring external skills to their tracked ref
ivar skill detach commit-style # turn an external skill into an authored one
ivar skill remove commit-style

Materialise

ivar skill sync

Writes the hall's skills into the native location each tool expects. This is the same step ivar sync performs as part of bringing a checkout in line with the manifest, and the seam a harness uses when it materialises agent config: a subprocess plus a filesystem convention, nothing more.

Inspect

ivar skill list     # what is in the hall's shared skills directory
ivar skill status   # external, authored, or stale
ivar skill doctor   # broken links, missing refs, and suggested fixes