OpenAI API — November, 2025

November 1, 2025

GPT-5.1's debut marks significant advancements in code generation, agentic workflows, and faster responses, with a new 'none' reasoning default. Further additions include specialized gpt-5.1-codex models for agentic coding. Also featured are enhanced role-based access controls for finer organizational management, extended prompt cache retention for improved performance, and new DTMF support in the Realtime API.

Added

Added support for DTMF key presses in the Realtime API. You can now receive DTMF events while using a Realtime sideband connection. See docs here for more information.
Released GPT-5.1, the newest flagship model in the GPT-5 model family. GPT-5.1 is trained to be especially proficient in:
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.
Released enhanced role-based access controls (RBAC). Role-based access control (RBAC) lets you decide who can do what across your organization and projects—both through the API and in the Dashboard.
Released gpt-5.1-codex and gpt-5.1-codex-mini to the Responses API. GPT-5.1-Codex is a version of GPT-5.1 optimized for agentic coding tasks in Codex or similar environments. Read more here.
Released extended prompt cache retention. Extended prompt cache retention keeps cached prefixes active for longer, up to a maximum of 24 hours. Extended Prompt Caching works by offloading the key/value tensors to GPU-local storage when memory is full, significantly increasing the storage capacity available for caching.

Changed

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