“Agent Skills” sounds like a new model capability until Anthropic supplies the definition: folders containing instructions, scripts, and resources which Claude loads when relevant. They are Markdown files with a launch budget.
This is not a criticism of the abstraction. Files are portable, inspectable, and exactly the right way to package reusable context. It is criticism of an industry which needs to rediscover prompt managers every few months, give them another noun, and announce that the wall has moved.