Mistral Releases Leanstral 1.5: Open-Source Lean 4 Theorem Proving Agent
AccBalanced · x · 2026-07-06
Mistral has released Leanstral 1.5, an Apache-2.0 open-source Lean 4 theorem proving agent. Built on a 119B parameter MoE architecture, it is compact yet demonstrates outstanding proving capabilities. It was congratulated by the vLLM team and others, and is aimed at formal mathematical theorem proving.
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