I build a pretty popular LLM tool. I think learning when/how to use them is as big a mental hurdle as it was learning to google well or whether something is googlable or not.

In the realm of coding here are a few things its really good at:

- Translating code, generating cross language clients. I'll feed it a golang single file API backend and tell it to generate the typescript client for that. You can add hints like e.g "use fetch", "allow each request method to have a header override", "keep it typesafe, use zod", etc

- Basic validation testing. It's pretty good at generating scaffold tests that do basic validation (Opus is good at writing trickier tests) as your building.

- Small module completion. I write an interface of a class/struct with it's methods and some comments and tell it to fill in. A recent one I did looked something like (abbreviated):

type CacheDir struct { dir string, maxObjectLifetime: Duration, fileLocks sync.Map }

type (cd *CacheDir) Get(...)

type (cd *CacheDir Set(...)

type (cd *CacheDir) startCleanLoop()

Opus does a really good job generating the code and basic validation tests for this.

One general tip: you have to be comfortable spending 5 minutes crafting a detailed query assuming the task takes longer than that. Which can be weird at first if you take yourself seriously as a human.

Note that I hadn't been able to do much of this with GPT-4 Turbo with with Claude Opus it really feels capable.