Building more with GPT-5.1-Codex-Max

Practical AI: Tools, Models & Frameworks

What changed

Introducing GPT-5.1-Codex-Max, a faster, more intelligent agentic coding model for Codex. The model is designed for long-running, project-scale work with enhanced reasoning and token efficiency.

Why it matters

A concrete addition to Practical AI: Tools, Models & Frameworks: it changes what's available to builders today rather than being general commentary.

How it compares

Related prior coverage to compare against:

  • Introducing Codex
  • Introducing GPT-5.2-Codex
  • Introducing GPT-5.3-Codex

Sources