The composer feature in Cursor in particular. If you don't know what it is, in a nutshell, you can describe an issue with the code or a new feature or whatever and it actually go and edit multiple files explaining what it is doing and how. You can follow-up with changes / discard them. And you can tell it which files are the context of the request
Another one: You can define rules for your project that are to be honored across the board, for instance you could say that every string has to be translated in English, Italian and French or that you want to use a particular library for some task etc.