GPT-5 Codex
A version of GPT-5 better at agentic coding
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GPT-5 Codex is a version of OpenAI's GPT-5 tuned specifically for agentic software engineering. It is built to work independently on real coding tasks, keeping context over long sessions, editing across files, running commands, and collaborating with a developer in real time.
It runs wherever development happens, including the terminal, an IDE extension, the web, and mobile, so a task can be started in one place and continued in another. Compared with earlier Codex, it is faster and more reliable on multi-step work.
It is aimed at developers who want to delegate substantial coding work, such as implementing features, fixing bugs, and refactoring, and review the results rather than write every line.
AI-assisted draft, human-reviewed before publishing — see how we choose & review tools.
Why we picked it
GPT-5 Codex earns its spot for keeping context over long sessions specifically — running wherever development happens, terminal, IDE, web, and mobile, with the same continuity is worth naming for a developer who moves between environments mid-task rather than staying in one place.
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