For me, AI code generation for F# has been pretty good! There's one annoying thing Opus/Sonnet do (honestly don't remember what other models do): use old syntax for array indexing.

  values.[index] // Old way of indexing required a .
  values[index] // Supported for awhile now

That's the "biggest" issue I run in to, and it's not that big of a deal to me.

Yesterday, it did try to hallucinate a function that doesn't exist; compilation failed, so the agent changed the function to a fold and everything was hunkey-dorey.