Moonshot's Kimi K3.1 Pro is a new open-weight model aimed at coding, game building and 3D modeling, with full weights promised by Nov 4.

On Friday, Oct 23, Moonshot AI released Kimi K3.1 Pro, the first model in its K3.1 series, and called it its "most capable 3T-class open-weight model" so far (Kimi on X).

It is a mixture-of-experts model, which means only part of it runs for each word it writes: 2.8 trillion parameters in total, 104 billion active at a time. It reads images as well as text and has a 1-million-token context window, enough to hold a large codebase or a stack of long documents. Moonshot also released K3.1 Pro Highspeed, which it says runs two to three times faster. Both are live today on Kimi.ai, Kimi Work, Kimi Code and the Kimi API, and Moonshot says "the full model weights will be released by Nov 4" (Kimi blog). On Terminal-Bench 4.0, a test of coding agents working in a terminal, Moonshot reports 65.7%, ahead of GPT-6 Astra at 58.2% and just behind Claude Opus 5.5 at 66.4%.

The 3D work is the unusual part. Moonshot says the model works across Unity, Unreal Engine and Godot, and can write and run scripts for Blender and CAD software without extra MCP connectors. On BenchCAD, which asks a model to rebuild 3D objects as CAD code, it scores 92.7% with tools, behind Opus 5.5 (96.2%) and GPT-6 Astra (95.9%).

A new 3D Make feature on kimi.ai and the Kimi app lets you preview and edit 3D models, download them ready for 3D printing, or export them as videos. Moonshot also says the claim-level hallucination rate on its own internal stress test fell from 23.4% for K3 to 8.3%, and that it removed cyber-attack data during training to limit hacking skills. Zero Data Retention is available for API customers. All of these scores come from Moonshot and haven't been checked independently yet.

Try it: if you build in Blender, Unity or Unreal, give K3.1 Pro a small, real task on kimi.ai, like scripting a simple scene or a game mechanic, and compare it with the model you use now. If you want to run it yourself, wait for the weights and their license, due by Nov 4.