It's the same. Every assumption, taste, doc, opinion, edge case, unstated knowledge, requirement, exception to the requirement, intention, should be provided for best results. It's not crucial for throwaway weekend projects, but for harder things, it is.

I find it to be the most challenging part. There's a large amount of unstated assumptions that you take for granted, and if you don't provide them all upfront, you'll need to regenerate the code, again and again. I now invest a lot of time into writing all this down before I generate any code.