"When AI reviews AI's code, you've built an infinite loop. Here's how we stopped it."

While building an AI code review product (Orange Codens), there was one design problem that dominated everything else: when the reviewer is AI and the fixer is AI, you can very easily build an infinite loop.

Walk it through. Orange reviews a PR and finds a problem. It doesn't stop at the comment — it hands the fix off to another Codens (Purple / Red) to produce a fix PR. But that fix PR is also a PR. Orange reviews it. New code, new findings. Hand off again. Fix. Review again.

A human reviewer stops at "good enough." AI doesn't, and every loop costs LLM tokens. So "it terminates" and "cost is bounded" have to be guaranteed by the architecture, not by how smart the model is. Here's what we wired into Orange, with the real code and the actual non-convergence incidents we hit.

The structure that loops

Built naively, here's how it spins: