OpenAI reports that enabling two specific API configurations significantly boosted GPT-5.6 performance on the ARC-AGI-3 benchmark. The improvements came from retaining reasoning traces and enabling output compaction, which together increased both accuracy and efficiency. This demonstrates how inference-time adjustments can yield substantial gains without model retraining.
- Enabling reasoning retention allows the model to preserve intermediate thought steps for better accuracy.
- Output compaction reduces token usage, improving inference efficiency alongside performance.
- Simple API config changes can yield massive benchmark gains without model weight updates.
- ARC-AGI-3 scores tripled, indicating high sensitivity to these specific inference parameters.