GPT-5.4 Pro became the first model to solve a researcher-level open problem in FrontierMath, a benchmark managed by Epoch AI. Claude Opus 4.6 and Gemini 3.1 Pro later solved it as well.
A summary of GPT-5.3 Instant’s hallucination reductions and safety regressions, GPT-5.4’s computer use, Tool Search, and 1M-token context, plus Saguaro’s 5× inference speedups.
