OpenAI Blog
Feb 5
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.
How Ramp engineers accelerate code review with Codex
How Ramp engineers use Codex with GPT-5. 5 to review code and ship improvements, allowing them to get substantive feedback in minutes instead of hours.
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OpenAI Blog
Jun 9
How engineers at Nextdoor use Codex to build without limits
How engineers at Nextdoor use Codex with GPT-5. 5 to investigate hard-to-reproduce issues, build across platforms, and focus on product outcomes.
OpenAI Blog
May 12
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.
OpenAI Blog
Nov 19, 2025
Building more with GPT-5.1-Codex-Max
Introducing GPT-5. 1-Codex-Max, a faster, more intelligent agentic coding model for Codex.
OpenAI Blog
May 29
How Braintrust turns customer requests into code with Codex
How Braintrust engineers use Codex with GPT-5. 5 to run experiments and code faster.
OpenAI Blog
Sep 25
Proaction boosts sales 60% and saves 75+ hours with Codex
Proaction leverages Codex, GPT‑Live‑1, and GPT‑6 Astra to accelerate the development, operation, and sales of modern fleet management solutions, achieving a 60% increase in sales and saving over 75 hours of work.
OpenAI Blog
Aug 7, 2025
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.
OpenAI Blog
Sep 15, 2025
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.
OpenAI Blog
Feb 5
GPT-5.3-Codex System Card
GPT‑5. 3-Codex is the most capable agentic coding model to date, combining the frontier coding performance of GPT‑5.
OpenAI Blog
Aug 7, 2025
First look at GPT-5
See how a group of leading developers use GPT-5 for the first time.
OpenAI Blog
Apr 23
Introducing GPT-5.5
Introducing GPT-5. 5, our smartest model yet—faster, more capable, and built for complex tasks like coding, research, and data analysis across tools.
OpenAI Blog
Apr 23
What is ChatGPT Codex?
Learn how ChatGPT Codex helps you go beyond chat by automating tasks, connecting tools, and producing real outputs like docs and dashboards.