This exact problem is something I’m hoping to fix with a tool that parses the source to AST and then has the LLM write code to modify the AST (which you then run to get your changes) rather than output code directly.
I’ve started in a narrow niche of python/flask webapps and constrained to that stack for now, but if you’re interested I’ve just opened it for signups: https://codeplusequalsai.com
Would love feedback! Especially if you see promising results in not getting huge refactors out of small change requests!
Interesting idea. But LLMs are trained on vast amount of "code as text" and tiny fraction of "code as AST"; wouldn't that significantly hurt the result quality?
Thanks and yeah that is a concern; however I have been getting quite good results from this AST approach, at least for building medium-complexity webapps. On the other hand though, this wasn't always true...the only OpenAI model that really works well is o3 series. Older models do write AST code but fail to do a good job because of the exact issue you mention, I suspect!
Having the LLM modify the AST seems like a great idea. Constraining an LLM to only generate valid code would be super interesting too. Hope this works out!
I’ve started in a narrow niche of python/flask webapps and constrained to that stack for now, but if you’re interested I’ve just opened it for signups: https://codeplusequalsai.com
Would love feedback! Especially if you see promising results in not getting huge refactors out of small change requests!
(Edit: I also blogged about how the AST idea works in case you're just that curious: https://codeplusequalsai.com/static/blog/prompting_llms_to_m...)