A prompt tells an agent what you want once. A skill teaches it how to do a whole class of task your way — and travels with you to the next project.
TL;DR
- Agent Skills are portable, structured packages of procedural knowledge.
- They encode how to do a task — steps, conventions, tools — not just what to do.
- Skills load on demand, keeping the agent's context lean until the knowledge is needed.
- They turn one-off expertise into reusable, shareable assets.
From prompts to skills
A prompt is ephemeral: you describe a task, the agent does it, the knowledge evaporates. That is fine for one-offs and wasteful for anything you do repeatedly. Every time you re-explain how your team writes a migration, structures a component, or runs a release, you are paying the same cost again.
A skill captures that procedural knowledge once, in a structured, reusable form the agent can load when relevant. It is the difference between telling a new hire how to do something every single time and writing it in the team handbook.
What a skill contains
A well-formed skill packages everything an agent needs to perform a task your way:
- When to use it — the trigger conditions, so the agent reaches for it at the right moment.
- The procedure — the steps, in order, with the decisions and conventions baked in.
- The context — examples, rules, and references specific to how you do the task.
- The tools — any scripts or capabilities the task depends on.
A prompt is intent. A skill is intent plus method plus the judgment of how your team actually does it — made reusable.
Dynamic loading keeps context lean
Skills connect directly to context engineering. Rather than stuffing every procedure into the agent's static context — expensive and distracting — skills are dynamic context: loaded only when the task calls for them. The agent carries a lightweight catalogue of what it can do, and pulls in the full procedure on demand. This keeps the context window focused while making a large library of know-how available.
Why skills are portable assets
The structured, self-contained nature of skills is what makes them valuable:
- Reusable across projects. A skill for "how we write a PR description" or "how we scaffold a service" travels with you.
- Shareable across a team. Encode an expert's process once and everyone's agent benefits.
- Composable. Complex work draws on several focused skills rather than one sprawling instruction blob.
- Versionable. Skills are artifacts you can review, improve, and track like any other code.
The takeaway
Skills are how procedural knowledge stops being something you re-explain and starts being something you own. They turn the tacit "how we do things here" into explicit, portable packages that make every agent interaction start further ahead. As agents take on more work, the teams that systematically capture their know-how as skills compound an advantage — their agents get better at their way of working with every skill they write.