GPT-6 Astra proves 70% of Lean theorems but solves none of 30 open conjectures

A new TCSExam benchmark from Tsinghua University and Moonshot AI finds frontier AI agents excel at formal proofs but stall on unsolved problems OpenAI’s GPT-6 Astra can now prove 70% of the theorems put in front of it in a new theoretical computer science benchmark. It also solved exactly zero of the 30 open conjectures it was handed. That split is the headline result of TCSExam, a benchmark built by researchers from Tsinghua University and Moonshot AI. What TCSExam actually measures TCSExam is a set of 100 tasks, each reviewed by experts, aimed at frontier AI agents working on theoretical computer science. The tasks are split into four tracks. The first is theorem proving in Lean. The second is solver engineering. The third is building constructions that beat existing human benchmarks. The fourth is the hard one: attempts to prove open conjectures. Lean is a formal proof language, which means a proof written in it has to satisfy a strict mechanical checker. Either the Lean kernel accepts the proof or it does not. Every submission gets verified by the Lean kernel or by a checker built for that specific task. A model that confidently produces a plausible but broken argument scores n...