Agent Skills

Agent Skills is an open standard for packaging reusable agent capabilities (instructions + resources) in a folder that tools can discover and load on demand. The format was originally developed by Anthropic and released publicly as an open specification in October 2025 (announcement, engineering blog). Treat the spec as actively evolving: implementations and best practices may change as more clients adopt it. Canonical definition: A simple, open format for giving agents new capabilities and expertise. ...