One thing that has worked for me when I have a long list of requirements / standards I want an LLM agent to stick to while executing a series of 5 instructions is to add extra steps at the end of the instructions like "6. check if any of the code standards are not met - if not, fix them and return to step 5" / "7. verify that no forbidden patterns from <list of things like no-op unit tests, n+1 query patterns, etc> exist in added code - if you find any, fix them and return to step 5" etc.

Often they're better at recognizing failures to stick to the rules and fixing the problems than they are at consistently following the rules in a single shot.

This does mean that often having an LLM agents so a thing works but is slower than just doing it myself. Still, I can sometimes kick off a workflow before joining a meeting, so maybe the hours I've spent playing with these tools will eventually pay for themselves in improved future productivity.