GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic workflows spanning software engineering, mathematics, and research.
GPT-5.1-Codex-Max delivers faster performance, improved reasoning, and higher token efficiency across the development lifecycle.
by Openai|400K context|$1.25/M input tokens|$10.00/M output tokens
Endpoints
Available providers for this model, with details on pricing, context limits, and real-time health metrics.
