OpenAI officially launches its latest generation of large language model series, GPT-5.6.

OpenAI officially launched the GPT-5.6 series of models, including the flagship Sol, the balanced Terra, and the cost-effective Luna, with API prices ranging from $1 to $30 per million tokens. In the Agents' Last Exam, Sol scored 53.6 points, surpassing Claude Fable 5 by 13.1 points, and its Programmable Agent Index reached a new high of 80 points, while significantly reducing both cost and time.