Eh, pretty much everyone that spent some time tweaking their harness already had a homemade 'ultracode' long before Anthropic did it.

OpenAI is just way more careful with what features they add or enable by default in their harness. Anthropic's harness is a junk drawer of random features, with a new feature added every few hours. It feels like they're in panic mode, dropping random things to see what sticks when models are eventually commoditized.

I prefer OpenAI way - slow and steady.