GPT-5.3-Codex System Card

Introducing GPT-5.3-Codex

GPT-5. 3-Codex is a Codex-native agent that pairs frontier coding performance with general reasoning to support long-horizon, real-world technical work.

Building more with GPT-5.1-Codex-Max

Introducing GPT-5. 1-Codex-Max, a faster, more intelligent agentic coding model for Codex.

Addendum to GPT-5 system card: GPT-5-Codex

This addendum to the GPT-5 system card shares a new model: GPT-5-Codex, a version of GPT-5 further optimized for agentic coding in Codex. GPT-5-Codex adjusts its thinking effort more dynamically based on task complexity, responding quickly to simple conversational queries or small tasks, while independently working for longer on more complex tasks.

Introducing GPT-5.2-Codex

GPT-5. 2-Codex is OpenAI’s most advanced coding model, offering long-horizon reasoning, large-scale code transformations, and enhanced cybersecurity capabilities.

GPT-5.1-Codex-Max System Card

This system card outlines the comprehensive safety measures implemented for GPT‑5. 1-CodexMax.

How NVIDIA engineers and researchers build with Codex

Teams use Codex with GPT-5. 5 to ship production systems and turn research ideas into runnable experiments.

GPT-5.4 Thinking System Card

Introducing GPT-5 for developers

Introducing GPT-5 in our API platform—offering high reasoning performance, new controls for devs, and best-in-class results on real coding tasks.

GPT-5.5 System Card

Addendum to o3 and o4-mini system card: Codex

Codex is a cloud-based coding agent. Codex is powered by codex-1, a version of OpenAI o3 optimized for software engineering.

Introducing GPT-5.2

GPT-5. 2 is our most advanced frontier model for everyday professional work, with state-of-the-art reasoning, long-context understanding, coding, and vision.

GPT-5 System Card

This GPT-5 system card explains how a unified model routing system powers fast and smart responses using gpt-5-main, gpt-5-thinking, and lightweight versions like gpt-5-thinking-nano, optimized for different tasks and developer use.