Agent Skills
An open format for packaging written instructions and workflows that an AI agent can load when it needs them.
An Agent Skill is a folder of written instructions that tells an AI agent how to do a particular job: the steps, the house rules, the file formats, whatever a new colleague would need to be told once. The agent loads it only when the task calls for it, which keeps the instructions out of the way the rest of the time. Created by Anthropic and published as an open standard, it has since been adopted more widely.
The appeal is that it needs no programming. A skill is mostly plain text, so the people who actually know a workflow can write one down without being developers. That also sets the limit: a skill shapes how an agent behaves and what it knows about your process, but it does not give the agent new abilities. For connecting to live tools and data you need an MCP server instead.