What is an Agent Skills?

Rather than hard-coding every possible action into an agent's core prompt, skills let a platform attach capability on demand: a markdown file describing how to use a provider's API, what authentication mode it needs, and how to verify the connection actually works. This keeps the agent's base context lean while letting it pick up dozens of integrations as needed. A well-built skill declares its boundaries explicitly, what it does and does not do, its auth mode (API key, OAuth, service account), required binaries or tools, and exact verification commands so the platform can confirm a connection is truly usable rather than just nominally present. Skills are typically versioned and stored in a canonical source location so behavior stays deterministic no matter which container or session loads them.