I use the AGENTS.md to show it how i want the code to look like. Something like "when implementing hooks adhere to the guidelines in docs/react-hooks.md". And then react-hooks describes your heuristics and what you consider best practices. There is a clear difference in code quality for me when using codex with a well crafted AGENTS.md vs. without one, you can run the experiment yourself pretty easily. As I mentioned in another comment, I think Claude poisoned users to stop relying on their Claude.md files and new codex users might be surprised at how well it adheres to guidelines.
replyWe use skills for similar purposes, with positive and negative examples.
replyI think it sometimes worked, for example for testing preferences, but sometimes it did not.
Could be a problem with the harness also.
In any case, I feel that it's a bit playing whac-a-mole with explicit rules for things that a more intelligent model should do by default.