They can produce idioms that resemble the flow of Forth code but when asked to produce a working algorithm, they get lost very quickly because there's a combination of reading "backwards" (push order) and forwards (execution order) needed to maintain context. At any time a real Forth program may inject a word into the stack flow that completely alters the meaning of following words, so reading and debugging Forth are nearly the same thing - you have to walk through the execution step by step unless you've intentionally made patterns that will decouple context - and when you do, you've also entered into developing syntax and the LLM won't have training data on that.

I suggest using Rosetta Code as a learning resource for Forth idioms.

Thanks for your reply. In fact, I've grown tired of programming by myself — I do 95% of my coding with Claude Code. But the remaining 5% of bugs can't be solved by the AI agent, which forces me to step in myself. In those cases, I'm thrown into a codebase I've never touched before, and code readability becomes key. That's what drew me to this article and to Forth. I would look into the Rosetta.