A skill is a saved instruction file, usually plain markdown (a simple text format), that teaches an agent how to run a repeatable workflow. It’s close to a prompt with more durability: a prompt is what you say right now, a skill is what you save because you’ll need it again. Skills sit between project instructions and a full application: project instructions set standing rules for the whole project, while a skill teaches one task, like transcript processing or client email drafting.
A recipe is the everyday version. You cook the meal once, write down the process, then reuse it with different ingredients. The recipe stays stable while the ingredients change: this week’s client files, transcripts, and examples.
Why you care
Build skills from real work: do the task manually with the agent, correct it, run it again with variation, then have the agent write the skill and test it before sharing. When skills multiply, ask which part is the reusable workflow and which part is context. Fully deterministic work with no judgment may want a script instead. Skills are shareable files, so a bad rule inside one carries bad instructions; treat an outside skill like a procedure someone handed your team.