The ARC-AGI-3 harness was throwing away reasoning tokens between turns. This is very bad harness design.

The models are designed to keep the reasoning tokens separate from the output and only publicly emit tool calls and the sometimes a summary of the reasoning tokens. The models are trained to depend on those private reasoning tokens. You can’t just delete them.

https://openai.com/index/how-two-settings-tripled-our-arc-ag...