Comment by watchdog408

A skill is more like a packaging convention around instructions, with the difference that the runtime knows it's a reusable unit. That lets it expose only the skill's name/description initially and load the full instructions (and sometimes bundled scripts or other resources) only when needed. Truth is that if you implemented the same lazy behavior with AGENTS.md and a bunch of Markdown files you'd end up with something that is functionally very close to a skills system.