GPT-5.1 released, with a new none reasoning default for faster responses

Released GPT-5.1, the newest flagship model in the GPT-5 model family. GPT-5.1 is trained to be especially proficient in:

• Steerability and faster responses when less thinking's required
• Code generation and coding use cases
• Agentic workflows

Note that GPT-5.1 defaults to a new none reasoning setting for faster responses when less thinking's required—different from the previous medium default setting in GPT-5.