So maybe describe the problem and work first on a means to detect errors, second - then let it rip.

I use the pi-mono coding agent with several different new open models running locally.

The simpler and more precise the prompt the better it works. Some examples:

"Review all golang code files in this folder. Look for refactor opportunities that make the code simpler, shorter, easier to understand and easier to maintain, while not changing the logic, correctness or functionality of the code. Do not modify any code; only describe potential refactor changes."

After it lists a bunch of potential changes, it's then enough to write "Implement finding 4. XYZ" and sometimes add "Do not make any other changes" to keep the resulting agent actions focused.