GPT5_1CodexMax
GPT-5.1-Codex-Max GPT‑5.1-Codex-Max is purpose-built for agentic coding. It's only available in the Responses API.
400,000 context window 128,000 max output tokens Sep 30, 2024 knowledge cutoff Reasoning token support
GPT-5.1-Codex-Max GPT‑5.1-Codex-Max is purpose-built for agentic coding. It's only available in the Responses API.
400,000 context window 128,000 max output tokens Sep 30, 2024 knowledge cutoff Reasoning token support