The company describes Pro as a 3T-class open-weight model with a one-million-token context window; Highspeed is claimed to deliver two to three times the speed. Both are available now through Kimi.com, Kimi Work, Kimi Code, and the Kimi API. Moonshot says full model weights will be released by November 4.
The accompanying technical post also describes cyber-risk controls for the planned open-weight release. Moonshot says it found cyber-related content in its mid-training corpus and cyber-related tasks in its reinforcement-learning environment mix as vulnerability-research performance increased. It says it removed that material from both stages while retaining general-purpose coding tasks.
Moonshot states that it does not intend to release open weights that extend the absolute frontier of cyber capability, and that K3.1 Pro's offensive cyber capability is deliberately below what its training pipeline could otherwise produce. The post does not provide an independent assessment of the filtering, a reproducible measurement of the resulting capability limit, or evidence that the controls prevent misuse after weights are released.