OpenAI releases GPT-5.3-Codex to the Responses API
OpenAI has made GPT-5.3-Codex available through its Responses API. The release note is minimal, providing no benchmark claims or capability details beyond the availability announcement. GPT-5.3-Codex appears to be a code-specialized variant in the GPT-5 family.
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OpenAI releases GPT-5.2-Codex to Responses API
OpenAI has released GPT-5.2-Codex via the Responses API, a variant of GPT-5.2 specifically optimized for agentic coding tasks in Codex and similar environments. The release extends the GPT-5.2 model family with a coding-specialized deployment. This is a tier-1 announcement from OpenAI's official release notes.
OpenAI makes GPT-5.2-Codex available via API
OpenAI has released GPT-5.2-Codex to the API and for users accessing Codex with an API key. The announcement is brief, with no benchmark claims or capability details disclosed. This extends API access to a coding-specialized variant of GPT-5.2.
Introducing GPT-5.3-Codex
OpenAI has announced GPT-5.3-Codex, described as a Codex-native agent combining frontier coding performance with general reasoning capabilities. The model is designed to support long-horizon, real-world technical work. The announcement positions it as an agentic coding system rather than a standalone language model.
Introducing GPT-5.2-Codex
OpenAI has released GPT-5.2-Codex, described as their most advanced coding model. The model features long-horizon reasoning, large-scale code transformation capabilities, and enhanced cybersecurity features. This represents a specialized coding-focused model in the GPT-5 family.
OpenAI releases GPT-5.3-Codex, upgraded agentic coding model with faster inference and real-time steering
OpenAI released GPT-5.3-Codex, an incremental upgrade to GPT-5.2-Codex targeting complex software engineering tasks. The new model runs 25% faster, improves reasoning and professional knowledge, and adds better real-time collaboration features including progress updates and in-session steering. It is available immediately across ChatGPT paid plans via the Codex app, CLI, IDE extension, and Codex Cloud, with API access forthcoming.
OpenAI releases GPT-5-Codex: GPT-5 variant optimized for agentic coding
OpenAI has published an addendum to the GPT-5 system card introducing GPT-5-Codex, a version of GPT-5 specifically optimized for agentic coding within the Codex environment. The model features dynamic thinking-effort adjustment, scaling compute based on task complexity—responding quickly to simple queries while sustaining longer independent work on complex coding tasks. This represents a specialized derivative of GPT-5 targeting software engineering agents rather than general-purpose use.
GPT-5.3-Codex System Card
OpenAI has released the system card for GPT-5.3-Codex, described as the most capable agentic coding model to date. It combines the frontier coding performance of GPT-5.2-Codex with the reasoning and professional knowledge capabilities of GPT-5.2. The release represents a continuation of OpenAI's Codex line of specialized coding models within the GPT-5 family.
OpenAI releases GPT-5.4 in Codex with native computer-use and 1M context window
OpenAI has made GPT-5.4 available across all Codex surfaces — the app, CLI, IDE extension, and Codex Cloud — positioning it as the recommended model for most Codex tasks. GPT-5.4 is the first general-purpose model in Codex with native computer-use capabilities and experimental support for a 1M token context window. The release also includes stronger tool use and tool search for agentic workflows, and the model is available via API.