Skills
What is the difference between a skill, a tool, and a prompt?
These three get confused: a one-off prompt is retyped each turn, a tool gives the agent access to a capability, and a skill gives it the procedural method for using that capability well.
These three get confused, so it is worth being precise.
- A one-off prompt is retyped every time and disappears after the turn.
- A tool (see tool use and MCP) gives the agent access to a capability.
- A skill gives the agent the method: the procedural knowledge for using that capability well in your situation.
One comparison puts the distinction sharply: a system prompt is static text loaded once at session start, while a skill is a file-based module the agent discovers, evaluates for relevance, and loads dynamically, including code it can run.[1] The same guide notes that an integration gives a model access to a tool but not the procedural knowledge of how to use it for your workflow; skills supply that method.[1]
A skill can run code Because a skill can bundle and execute scripts, only install skills from sources you trust, and look at the bundled files the way you would review any dependency.