What is an agent skill?
Skills are .md files that give an AI agent persistent instructions — loaded automatically every time the agent runs. Because they execute silently with full agent access, a poorly written or malicious skill can cause serious harm.
Loaded automatically
Skills run on every agent session without you needing to invoke them.
Can contain risky commands
A skill can instruct the agent to run shell commands, access files, or call external APIs.
Affect every AI action
Instructions in a skill shape every response the agent gives, overriding its defaults.