MCP & Tooling
Agent Skill
Also: skill, SKILL.md
A packaged set of instructions, and sometimes scripts, that an agent loads to learn how to do a specific task.
In more detail
Skills make agents better at focused jobs and also add code and instructions you did not write. A skill can tell the agent to run commands, and bundled scripts execute with the agent's permissions. Review a skill like a dependency: read what it says, check what it runs, and prefer sources you can verify.