OpenAI releases the GPT-5.6 series model.

The United States' Open Artificial Intelligence Research Center announced on the 9th that it officially launched the GPT-5.6 series model, which will gradually be open for use in ChatGPT, Codex, and OpenAI API starting today. The company stated in a release on its official website that the GPT-5.6 series includes three model versions: the flagship model Sol, the balanced model Terra adapted for daily office use, and the fastest and lowest cost model Luna. According to the statement, GPT-5.6 has added capabilities such as "max" and "ultra". The former allows the model to spend more time on reasoning, exploring alternative solutions, checking and correcting methods; while the latter defaults to coordinating four agents to parallel process complex tasks, exchanging higher word oxygen usage for stronger results and shortening the completion time of high-difficulty tasks.