Why skills instead of instructions
An agent’s instructions describe what it is. A skill describes how a particular job is done. Keeping them apart buys you three things:- Reuse. One escalation procedure, attached to every agent that might need it.
- Change without redeploy. Publishing a new version of a skill updates the agents attached to it. Nothing restarts.
- Attribution. A run records which skills were available to it and which it actually used, so you can tell a procedure that helps from one that is never opened.
The two kinds
Skills lists both, and the kind filter separates them.
Authored skills are the ones you manage as a library. Self-reported skills are visible so that you
can see what your workers are carrying — and if you want to take one under management, Claim as
authored copies it into the registry and versions it from then on.
Author a skill
1
Open Skills and create one
Go to Skills and press Create skill.
2
Name it for the job it does
Name and Description are what an agent sees when deciding whether a skill is relevant, so
write the description as a one-line statement of when to use it — not a title restated.
3
Write the content
SKILL.md content is Markdown. Say what the agent should do and when, concretely: the checks
to run, the order to run them in, the thresholds that matter, what to do with the result.
4
Label it
Labels are key/value metadata. They group the library and can be used to control who sees a
skill.
5
Create it
Creating with content publishes version 1.
Authoring in a worker’s repository instead
If you would rather keep a skill next to the code that uses it, put it in the worker’sskills/
directory and it registers when the worker connects. Two layouts work:
This is the same
SKILL.md convention Claude Code uses, and a worker also reads a .claude/skills
directory if it finds one. Skills you already keep for a coding agent transfer as a copy — no format
change.Versions
Authored skills are versioned with plain increasing integers, and the distinction that matters is what does and does not create a version:
Rollback is append-only on purpose. Version history stays a true record of what was in force when,
which is what makes it useful for auditing a run that happened three weeks ago.
Attach a skill to an agent
Attaching is a binding between an agent and a skill, and it carries one decision: track latest, or pin a version.
Three places attach a skill, and they write the same binding:
- From the skill — the Currently attached list on the skill’s editor.
- From the agent — its Skills & tools tab, using Attach a skill.
- While creating the agent — the wizard’s skills section.
Declared versus discovered, on the agent
An agent’s Skills & tools tab splits its skills the same way:- Declared — explicitly attached and versioned. These are the ones you manage.
- Discovered — self-reported by the running agent. Promote to declared brings one under management.
How an agent finds the right skill at run time
Skills are not all pasted into the prompt. An agent gets a short index of everything attached to it — each skill’s name, description, and tags — and the content of the most relevant few. The rest are available for the agent to open during the run when it decides it needs them. Two consequences for how you write them:- The description is the routing decision. It is what the agent reads when choosing, so a vague description means a skill that never gets opened.
- Long skills are fine. Length costs nothing until the skill is actually loaded, so put the detail in rather than compressing it into something ambiguous.
A published version reaches a running agent on its next run. Skills reload live — unlike an agent’s
instructions or its tool configuration, a skill change does not need a restart.
See which skills a run used
Open a run and look at its Skills card. It lists every skill that was available to the run and marks the ones the agent actually invoked. Over time this is the honest signal about your library: skills that are consistently available but never used are either badly described or not needed. Skills are also graded alongside your agents — Skills sorts by rating, and a skill that has not been graded says so. See Evaluations.Delete a skill
Deleting is refused while a skill is still attached to an agent — detach it first. Once deleted, the skill and its version history are removed from the library while the runs that used it keep their record of having done so.Next steps
Knowledge base
Skills tell an agent how to work; the knowledge base tells it what you know.
Build from scratch
Ship skills alongside an agent you author.
Manage a deployed agent
Attach and repin skills on a live agent.
Evaluations
How a skill’s contribution gets graded.