It greatly depends on the type of work you are trying to delegate to the AI. If you ask it to add one entire feature at a time, file level could work better. But the time and costs go up very fast, and it's harder to review.
What works for me (adding features to huge interconnected projects), is think what classes, algorithms and interfaces I want to add, and then give very brief prompts like "split class into abstract base + child like this" and "add another child supporting x,y and z".
So, I still make all the key decisions myself, but I get to skip typing the most annoying and repetitive parts. Also, the code don't look much different from what I could have written by hand, just gets done about 5x faster.
What works for me (adding features to huge interconnected projects), is think what classes, algorithms and interfaces I want to add, and then give very brief prompts like "split class into abstract base + child like this" and "add another child supporting x,y and z".
So, I still make all the key decisions myself, but I get to skip typing the most annoying and repetitive parts. Also, the code don't look much different from what I could have written by hand, just gets done about 5x faster.