The new GPT-5.6 family: Luna, Terra, Sol

OpenAI's GPT-5.6 family launches in three sizes—Luna ($1/$6 per 1M tokens), Terra ($2.50/$15), and Sol ($5/$30)—with a 1M token context window and 128K max output tokens. Sol achieves 53.6 on Agents' Last Exam, beating Claude Fable 5 by 13.1 points, while OpenAI published a critique noting ~30% of SWE-Bench Pro tasks are broken.