GPT‑5‑Codex Rolls Out

OpenAI has added GPT-5-codex, a GPT-5 variant built for coding agents, and made it the default model for Codex cloud tasks and code review. (help.openai.com) OpenAI disclosed the change in ChatGPT Business release notes published last week, saying GPT-5-codex is now available “everywhere you use Codex.” That includes cloud jobs, code review, the Codex command-line tool, and the integrated development environment extension. (help.openai.com) A coding agent is a model that can inspect files, propose edits, run commands, and work through a software task in steps instead of answering with a single block of text. OpenAI’s Codex product is the company’s coding agent surface, and its command-line tool runs in a terminal on macOS and Linux, with Windows support still marked experimental. (help.openai.com) OpenAI is describing this as a model-family extension inside Codex, not as a broad relaunch of GPT-5 across ChatGPT. The company’s separate model release notes use similar language, calling GPT-5-codex “a GPT-5 variant optimized for agentic coding in Codex.” (help.openai.com) That wording fits how OpenAI has been splitting its recent model lineup by job: general-use ChatGPT models on one side, and coding-tuned variants inside developer tools on the other. In its current API documentation, OpenAI separately lists GPT-5.3-Codex as a model “optimized for agentic coding tasks in Codex or similar environments.” (developers.openai.com) The practical change is about defaults and reach. Teams using Codex in the cloud now get GPT-5-codex for task execution and review by default, while developers working locally can choose it in the Codex command-line interface and integrated development environment extension instead of being limited to cloud-only access. (help.openai.com) OpenAI has also been building out the surrounding Codex stack rather than treating it as a single chat feature. Its developer materials now include a Codex prompting guide for direct application programming interface use, and the open-source Codex repository describes the tool as a lightweight coding agent that runs in the terminal. (developers.openai.com) (github.com) The release landed alongside business changes around Codex, including a $5 per month cut in subscription-based ChatGPT seat pricing for affected plans and an updated Codex rate card tied to token-based usage. ChatGPT pricing itself was unchanged. (help.openai.com) The result is a narrower but clearer launch: OpenAI moved a coding-specific GPT-5 variant into the default path for software work, while leaving its broader ChatGPT model lineup on a separate track. (help.openai.com)