What I find works really well: scaffold the method signature and write your intent in the comment for the inputs, outputs, and any mutations/business logic + instructions on approach.

LLM has very high chance of on shotting this and doing it well.

This is what I tend to do. I still feel like my expertise in architecting the software and abstractions is like 10x better than I've seen an LLM do. I'll ask it to do X, and then ask it to do Y, and then ask it to do Z, and it'll give you the most junior looking code ever. No real thought on abstractions, maybe you'll just get the logic split into different functions if you're lucky. But no big picture thinking, even if I prompt it well it'll then create bad abstractions that expose too much information.

So eventually it gets to the point where I'm basically explaining to it what interfaces to abstract, what should be an implementation detail and what can be exposed to the wider system, what the method signatures should look like, etc.

So I had a better experience when I just wrote the code myself at a very high level. I know what the big picture look of the software will be. What types I need, what interfaces I need, what different implementations of something I need. So I'll create them as stubs. The types will have no fields, the functions will have no body, and they'll just have simple comments explaining what they should do. Then I ask the LLM to write the implementation of the types and functions.

And to be fair, this is the approach I have taken for a very long time now. But when a new more powerful model is released, I will try and get it to solve these types of day to day problems from just prompts alone and it still isn't there yet.

It's one of the biggest issues with LLM first software development from what I've seen. LLMs will happily just build upon bad foundations and getting them to "think" about refactoring the code to add a new feature takes a lot of prompting effort that most people just don't have. So they will stack change upon change upon change and sure, it works. But the code becomes absolutely unmaintainable. LLM purists will argue that the code is fine because it's only going to be read by an LLM but I'm not convinced. Bad code definitely confuses the LLMs more.

What if I write the main function but stub out calls to functions that don't exist yet; how will it do with inferring what's missing?