Moonshot AI · Open-Weight Frontier

Kimi K3.1 Pro

The first model in Moonshot's K3.1 series, a post-trained version of Kimi K3 with larger reinforcement-learning compute, a 1M-token context and a Highspeed variant 2-3x faster. Moonshot reports 65.7% on Terminal-Bench 4.0 against 58.2% for GPT-6 Astra and 66.4% for Claude Opus 5.5, 92.7% on BenchCAD with tools and 64.4 on OfficeQA Pro v2, all self-reported. Its internal hallucination rate fell from 23.4% to 8.3%. For the open-weight release it removed cyber-related training data, cutting an internal exploit benchmark score from 90.5% to 81.0%. It is live on Kimi.ai, Kimi Work, Kimi Code and the API; weights are due by 4 November. Follows Kimi K3 (weights) covered in week 31.