Moonshot AI reported Kimi K3.1 Pro scored 65.7% on the Terminal-Bench 4.0 coding benchmark, against 66.4% for Anthropic's Claude Opus 5.5 and 58.2% for OpenAI's GPT-6 Astra

Moonshot AI's launch post for Kimi K3.1 Pro, a 3T-class model with a 1-million-token context window and a faster Highspeed variant, with benchmark results and an account of removing cyberattack-related training data before the open-weights release.