Agent Skills
Also written as Claude Skills, SKILL.md
Packaged instructions, scripts and reference files that an AI agent loads only when a task needs them — for example, 'how our company formats a sales report'. Introduced by Anthropic in 2025 and published as an open format other tools have adopted. They let teams give agents specialised know-how without cramming everything into one long prompt.
Think of it like
A shelf of instruction manuals the assistant takes down only when the job calls for one.
Junior or senior?
Very new, so look for what was built rather than years.
Senior sounds like
Has written skills other people use and can explain how they tested that the agent picked the right one at the right time.
Ask them
“What skill did you build, who used it, and how did you check the agent used it correctly?”