GPT 5.3 Codex is now on AI Gateway
GPT-5.3 Codex just shipped on AI Gateway — 25% faster, built for agents running production workflows end-to-end.
Why it matters
Vercel's AI Gateway now surfaces a new reasoning+coding hybrid model optimized for agentic software development work. For founders building AI-native dev tools, this is a capability milestone that changes what's possible in code generation and multi-step task execution.
The key facts
6 to knowGPT-5.3 Codex combines GPT-5.2-Codex coding strengths with GPT-5.2 reasoning depth
25% faster and more token-efficient than prior versions
Designed for long-running agentic work: research, tool use, multi-step execution
Mid-task steering without context loss
Better handling of underspecified prompts for web development
Available via Vercel AI Gateway with unified API, cost tracking, observability, and intelligent provider routing
Go to the source
Vercel Blogvercel.com
Publisher excerpt: GPT 5.3 Codex is now available on AI Gateway. GPT 5.3 Codex brings together the coding strengths of GPT-5.2-Codex and the reasoning depth of GPT-5.2 in a single model that's 25% faster and more token-efficient. Built for long-running agentic work, the model handles research, tool use, and…