OpenAI this week rolled out GPT-5.1-Codex-Max, a new agentic coding model, built for long-running and detailed software development tasks.<\/p>\n
Described as \u201cfaster, more intelligent, and more token-efficient at every stage of the development cycle,\u201d the new model is available across all Codex surfaces.<\/p>\n
This launch comes shortly after Google unveiled Antigravity<\/a>, its agentic, developer-focused AI platform, setting the stage for a head-to-head battle between the two biggest players in AI for the future of software development.<\/p>\n What is GPT-5.1-Codex-Max<\/p>\n Codex Max is OpenAI\u2019s newest and most advanced coding model, built on top of the GPT-5.1 architecture. The model was trained using real software engineering work \u2014 things like creating pull requests, reviewing code, building websites and answering technical questions.<\/p>\n Because of these features, it performs better than OpenAI’s previous coding models on frontier coding evaluations. It is also more useful in everyday situations, as GPT\u20115.1-Codex-Max is the first version that can work smoothly in Windows, and it was trained to be a much better teammate when using the Codex command-line tool, according to the company’s blog post.<\/p>\n Also Read | How will ads work on ChatGPT? OpenAI CEO just gave a major hint<\/a><\/p>\n OpenAI also said the model can work on its own for many hours at a stretch. In internal tests, Codex-Max kept improving its code, fixing errors, and ultimately deliver a successful result, even when the task ran for more than 24 hours.<\/p>\n CEO Sam Altman<\/a> praised the team behind rapid progress of the new model, calling them \u201cbeasts.\u201d<\/p>\n \u201cThe product\/model is already so good and will get much better; I believe they will create the best and most important product in the space, and enable so much downstream work,\u201d he wrote on X (formerly Twitter).<\/p>\n Who can access this new model?<\/p>\n The GPT-5.1-Codex-Max model is accessible to users on ChatGPT Plus, Pro, Business, Edu, and Enterprise plans. For developers using Codex CLI via the API key, the new model can be accessed when API support rolls out.<\/p>\n GPT-5.1-Codex-Max will now replace GPT-5.1-Codex as the default in all Codex interfaces.<\/p>\n OpenAI<\/a> also said that 95% of its internal engineering team uses Codex weekly and that engineers \u201cship roughly 70% more pull requests since adopting Codex.\u201d<\/p>\n Accuracy and efficiency<\/p>\n Open AI says GPT-5.1-Codex-Max is much better than the previous versions. In one coding test (SWE-Lancer), it got 79.9% of answers right, compared with 66.3% with the older GPT-5.1-Codex.<\/p>\n In another test (SWE-bench Verified), the newer model solved more problems with higher accuracy at the same reasoning level while using about 30% lesser \u201cthinking tokens,\u201d meaning it works faster and more efficiently.<\/p>\n Also Read | Sam Altman\u2019s memo flags tough times ahead amid Google\u2019s AI revival: Report<\/a><\/p>\n