How to use the agent skill

anvil ships an agent skill at skills/make-animation/SKILL.md. Registering it with your agent harness lets you ask for animations in plain language; the agent emits a valid SceneSpec and drops <Anvil> on the page.

Register the skill¶

Copy or symlink the skill into your harness's skills directory, then reload. The skill's front-matter description is what triggers it — phrases like “add a loading spinner” or “make a 3D hero scene.”

Ask for an animation¶

Examples the skill is tuned for:

"add a loading spinner in brand blue"
"flash a green success check when the deploy lands"
"make a 3D hero with a spinning knot and put it on the page"
"render a particle starfield"

The agent picks lottie for flat vector motion and three for 3-D, generates the spec, and validates it. The reasoning behind that split is in About choosing Lottie and three.js.