Skills

Package instructions and the tools they need into a reusable, publishable playbook.

A skill is a named playbook: instructions, the tools those instructions assume, and phrases that should bring it to mind. Attach one to an agent and the behaviour travels with the skill instead of being copy-pasted into a system prompt.

Use a skill when the same procedure shows up across agents, when a procedure is too long to sit in instructions all the time, or when you want to publish something other people can install.

Anatomy

Field	Purpose
`slug`	Stable identifier — how it is installed and referenced
`name` · `description`	What a human sees when browsing
`instructions`	The playbook itself, in Markdown
`tools`	Tool names the instructions rely on
`triggers`	Phrases that should surface the skill
`tags` · `icon`	Discovery and display
`isPublic`	Whether it appears in the public index

Create one

agc skills create \
  --slug weekly-report \
  --name "Weekly report" \
  --description "Produce the standard weekly status report" \
  --instructions "$(cat weekly-report.md)" \
  --tools webSearch,createDocumentFile \
  --triggers "weekly report,status update" \
  --icon 📊

Attach to an agent

await commons.skills.setAgentAvailability(skill.skillId, agentId, true);
const { data: attached } = await commons.skills.listForAgent(agentId);

Attached skills appear in the agent's index. When one matches, the agent calls invoke_skill to load the full instructions — so a dozen skills cost a few lines of context each until one is actually needed.

Progressive disclosure

agc skills index

The index is name, description, and triggers only. It is what the model sees by default; the body arrives on demand. That is what keeps a large skill library cheap.

Write triggers the way a user would phrase the request, not the way you would name the feature.

Publish and install

agc skills publish weekly-report
agc skills install weekly-report > SKILL.md
agc skills unpublish weekly-report

install prints the full skill as Markdown, which makes a published skill portable to any agent framework that reads a SKILL.md.

Writing skills that work

One job per skill. "Weekly report" beats "reporting".
Number the steps. Ordered instructions are followed more reliably.
Name the tools inline. "Write it up with createDocumentFile" beats hoping the model picks the right one.
Say what done looks like. A skill that ends with a check gets checked.
Version through the slug — invoice-review-v2 — so agents on the old one keep working.

Manage

agc skills list --owner <id>
agc skills get <skillId>
agc skills update weekly-report --description "…" --tools webSearch,createPdfFile
agc skills delete weekly-report --yes

update replaces list fields wholesale — pass the complete --tools, --triggers, or --tags you want, not just additions.