I used Opus 5.5 to figure out that a language model we were serving at work for internal use (we don't really serve models, we only use this internally because it processes sensitive data that we can't send to external endpoints) was being bottlenecked by CPU contention on tokenization, by having Opus run in an autoresearch style loop.

Opus's first proposal for a fix was to spawn multiple Python processes and build a load balancer between them in Python. At first I asked it why it wasn't using haproxy and it said that haproxy would be an added dependency and that the overhead for this kind of thing in Python would be negligible. I knew this was idiotic but wanted to test this out, so had Opus run two experiments in parallel. Sure enough an haproxy load balancer was much, much better on HTTP load balancing than Python code was.

This is the kind of thing that if you're unfamiliar with how networking code works, the models can autopilot into bad decisions that are verifiably correct (higher throughput than the original CPU-bottlenecked implementation) but much short of best practice.