Reading up on Periodic Harness

Periodic Labs trained Periodic Neon on in-house lab data via midtraining and RL, achieving a 55.3% success rate on FrontierXRD—a 20x improvement over Kimi K2.6—at lower cost than frontier models like GPT-6 Astra and Claude Fable 5.1, with gains from a scientific harness and LLM-judge rewards.