OpenAI launches Codex MacOS app with GPT-5.3 model to challenge Claude Code dominance
OpenAI released a new MacOS app for Codex, its AI coding tool, alongside the GPT-5.3-Codex model that runs 25% faster than previous versions. The launch marks OpenAI's push to catch up with Anthropic's Claude Code, which has dominated the agentic coding market and reached $1 billion in annualized revenue within six months of public release.