Author a skill

Teach your agent a repeating task, as a skill it loads only when a request matches.

Write a skill after you have done the same multi-step task three times, never speculatively.

Create the skill

Add a SKILL.md file in a folder under your pack:

packs/<pack>/.apm/skills/<name>/SKILL.md

The file opens with frontmatter, a settings block. Give it a kebab-case name and a one-line description that starts with “Use when” and names the trigger, because your agent reads the description to decide when to load the skill. Below it, write the steps your agent should follow.

Rebuild and lint

Edit the source under packs/, never the copy under .claude/skills/, then regenerate the copies and lint:

make build-self && agentbundle catalogue lint --root .

The linter checks the frontmatter and the projected copy, and tells you what to fix.

Test that it activates

List prompts that should and should not trigger the skill in evals/eval_queries.json, then run them:

agentbundle pack evals run --pack <name>

A miss means the description should name its trigger more precisely.

Next, author a subagent. Every rule on body structure, scripts, dependencies, and evals is in Skill authoring standards.