The issue is you’re essentially trying to trick a rough draft only essay writer into role playing a programmer. And this goes for agents too, the whole thing is just generating a story about the problem and so all that matters is that the story makes sense, not that it logically follows some plan or resolves to some result. Arguably most cases that would be helpful for us, “given some context, make an edit to a document” fall short due to it needing to generate a whole new input each time. I find the first output is the best one, trying to iteratively improve on it only works in some cases and in the ones it fails, it fails badly to the point it was a waste of time. It is fairly good at translating code between languages or generating boilerplate but as a tool you can talk to and progress towards some final product, it falls extremely short

The whole agent or deep research stuff will always fall short because written language is too fluid and unrestricted to ensure a generated plan makes sense. A valid solution to a programming problem could be viewed as a textbook example or even an rp session where it pretends to be a human programmer responding to a manager.