GPT-5.1-Codex-Max
by OpenAI
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 reasonin
Models
GPT-5.1-Codex-Max
Added 10 July 2026
Overview
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...
How to use / API access
Call via OpenRouter with model id `openai/gpt-5.1-codex-max`.
- openrouter ·
openai/gpt-5.1-codex-maxDocs
OpenRouter id: openai/gpt-5.1-codex-max
Notes
GPT-5.1-Codex-Max is listed in the EDNA Models directory from the OpenRouter catalogue.
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