A reusable playbook for an agent
An Agent Skill is a folder of instructions, scripts, and resources that teaches an AI agent how to complete a specialized task consistently. The key file is usually SKILL.md: a plain Markdown document containing a name, a description, and the workflow the agent should follow.
A skill is useful when the task requires more than a one-off prompt. It can preserve tool commands, validation steps, output standards, and domain-specific judgment so the agent does not have to reconstruct the process every time.
Skills and MCP solve different problems
A Skill mainly supplies procedural knowledge: what to do, in which order, and what a good result looks like. An MCP server mainly supplies a connection to external tools or data. The two often work together—a skill can teach the agent how to use an MCP connection safely and effectively.
What to check before installation
Read the source instructions, note every command and dependency, and understand which files, accounts, or services the skill can access. Popularity is evidence of interest, not proof of safety. Prefer public sources, narrow permissions, active maintenance, and installation steps you can verify.