Moonshot releases Kimi K3.1 Pro, with open weights due by 4 Nov

Moonshot has released Kimi K3.1 Pro, which it calls its most capable 3T-class open-weight model so far, with a 1-million-token context window, plus a Highspeed variant it says runs 2 to 3 times faster. It is available today on Kimi.ai, Kimi Work, Kimi Code and the Kimi API, and Moonshot says full model weights will be released by 4 November 2026. On Terminal-Bench 4.0, Moonshot reports 65.7% for K3.1 Pro, ahead of GPT-6 Astra at 58.2% and just behind Claude Opus 5.5 at 66.4%; those scores are Moonshot's, and for K3.1 Pro they used the Claude Code harness. Moonshot also says it removed cyber-related data from mid-training and RL for the open-weight release, cutting its score on an internal exploit benchmark from 90.5% to 81.0% at pass@3.