I am writing this not as an outside observer, but as a daily Codex user whose real project is being affected by this workflow. What I am experiencing is very clear: Codex keeps repeating the same mistakes in my project, even after I have explicitly emphasized the same constraints more than 20 times…

sounds like a skill issue. For instance, if a model does a mistake you normally want to start over and steer it away from repeating the mistake rather than tellig it to fix the mistake. Because that’s how LLMs work.

You may be right. Maybe building and maintaining a 900,000+ line project was just an accident and I somehow got here with no skill at all. But jokes aside, this is not about one mistake. It is about repeated constraint violations in a large project despite explicit instructions. That is a reliabili…

I think that is a very interesting observation. As complexity increases, it becomes increasingly difficult to steer the agent properly. How is the project harness set up? Did this issue appear only recently? Have there been any changes to the agents file or the skills? There can be many possible …

Could you elaborate on the issue a bit? What mistakes does it repeat? What is the project structure? 900,000 feels like a very large project to me. Is there any way you can split this up into separate repos? Does it have to be monolithic? I can attest to there being limits to context and some…

I have one project I maintain since 2015, about 750k lines. No issues, mostly because repeated “misbehavior” is usually a good sign for a deeper analysis and documentation/agent guidance update. How does your documentation looks like? How do you organize what gets into agent’s context window?

Good questions. To clarify, this is not an undocumented or lightly guided project. The codebase is around 900,000+ lines, and the documentation layer is very large as well. There are well over 2,000 documentation/spec/governance/evaluation/design-related files across the project. This includes arch…

Upon reading this the one thing I am not seeing noted: test cases. [image] Tips and Tricks for using Codex Codex It is also important to emphasize that 100% test coverage of the core code is essential. Yes, it is a significant amount of work, and yes, it can f…

I have a similar case right now. I once added an instruction to cover a situation that, in hindsight, was rather specific. When I tried to clarify the actual intention later, I realized it no longer worked as expected. Looking closely at the semantics, I can see that the instruction hints at the sp…

@Rotto The correct answer is the bot is inclined to do things a certain way, but it’s not a one sized fit all. For instance, I had issues with it relaunching after closing it, slipping back into the background and doing it again… So I changed the permissions for the app on my box, which means it’…

These are good points, and I think this is the right direction to analyze the problem. I asked Codex to inspect the repo instead of guessing, and the useful finding is this: the constraint is already documented in multiple places, including agent guidance and deterministic-rail related docs. So I d…

Why does Codex repeat the same mistakes?

Codex

EricGT June 13, 2026, 9:12pm 8

Upon reading this the one thing I am not seeing noted: test cases.

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Why does Codex repeat the same mistakes?

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