In a significant update, OpenAI has launched GPT-5.3 Codex, an agentic coding tool, just moments after Anthropic unveiled its own.
As per the company, the recently introduced model transforms Codex from an agent that can merely “write and review code” to one that is able to do “anything developers and professionals do on a computer, expanding who can build software and how work gets done.”
Notably, the ChatGPT manufacturer claimed that it can easily generate “highly functional complex games and apps from scratch over the course of days,” as it has already been tested against several performance benchmarks.
Additionally, the latest GPT-5.3 Codex is said to be 25% faster in contrast to its previous models and that it was the company’s first model that “was instrumental in creating itself.”
As mentioned earlier, the launch comes after on the heels of the latest agentic coding model released by its competitor, Anthropic.
Indeed, OpenAI and Anthropic had originally planned to release their two agentic coding tools at the exact same time: 10 a.m. PST. However, not long before the original launch time, Anthropic moved its launch date up by 15 minutes.
