Prompts → prompt libraries → skills → plugins → now bots. Every six months there's a new reusable unit everyone gets hyped about. Look under the hood of any of them and it's the same thing: Files and folders. That's it. Structured so the agent gets the right context at the right time, plus the right instructions, so you get what you actually wanted. Add a few scripts where it makes more sense to be deterministic than to ask the model. The packaging keeps changing. The core idea hasn't. If you know how to organize your work into good files and folders, you're already ahead of whatever gets launched next.