# Moonshot AI releases Kimi K3.1 Pro with open weights due November 4

> Original title: Moonshot AI’s first update, the new Kimi K3.1 Pro

- Source: Rohan Paul
- Published: 2026-10-23T19:21:53.000Z
- Bad Influence: https://badinfluence.news/items/fvphcfnpu93rtzshbxfyu9git
- Original: https://x.com/rohanpaul_ai/status/2113712534008262673

## Summary

Rohan Paul reposts Moonshot AI's announcement of Kimi K3.1 Pro, a 2.8T-parameter open-weight multimodal model with a 1M-token context. Moonshot says it scores 65.7% on Terminal-Bench 4.0, 0.7 points behind Claude Opus 5.5, and cuts hallucination in its internal test from 23.4% to 8.3%. The model is live on Kimi.ai and the API, with full weights due by November 4, 2026.

## Post

Moonshot AI’s first update, the new Kimi K3.1 Pro

> Kimi K3.1 Pro scores 65.7% on Terminal-Bench 4.0, 0.7 points behind Claude Opus 5.5 and 7.5 ahead of GPT-6 Astra, at a lower average cost per task than either rival’s top runs.

> Moonshot saw exploit skill climb as post-training scaled, so it removed cyber-related data from mid-training and RL; on its internal xdev-bench-hard, pass@3 fell from 90.5% to 81.0%.

> The filtered model still solves 81.0% of those exploitation tasks against K3’s 33.3%, which Moonshot reads as general coding gains carrying into cyber work, while a third-party run of GPT-5.6 Sol solved 100%.

> On Moonshot’s internal hallucination stress test with tools, false claims fell from 23.4% for K3 to 8.3%, still above GPT-6 Astra’s 5.5% but well below Claude Opus 5.5’s 15.0%.

> The biggest jump is on Moonshot’s simulated business-operation test, where scores rose from 8.9 to 37, and K3.1 Pro also tops OfficeQA Pro v2 at 64.4 against Opus 5.5’s 62.2.

> Gains are uneven: K3.1 Pro scores 38.1 on Terminal-Bench Science against GPT-6 Astra’s 68.1 and Opus 5.5’s 63.3, while leading Agents’ Last Exam at 43.2 and Humanity’s Last Exam with tools at 70.0.

> K3.1 Pro and a Highspeed variant running 2-3x faster are live in Kimi’s apps and API, with full weights due by November 4 for independent reruns.

![](https://badinfluence.news/api/img-proxy?u=https%3A%2F%2Fpbs.twimg.com%2Fmedia%2FHVVpUB_a4AAnlAb.jpg&mode=thumb&exp=1793404800&sig=5afebfabd072773d)

## Quoted post @Kimi_Moonshot

> Introducing Kimi K3.1 Pro: our most capable 3T-class open-weight model.
> 
> 🔹 1M-token context, 2.8T total / 104B active params (MoE), Multimodal.
> 🔹 Full-project coding: games in Unreal, Unity & Godot.
> 🔹 Excels at parametric 3D modeling in Blender & CAD.
> 🔹 More reliable at finance work: Accurate modeling with hallucination down by 65%.
> 🔹 Matching the strongest proprietary models across coding, agentic and knowledge benchmarks.
> 
> Kimi K3.1 Pro and K3.1 Pro Highspeed (2–3× faster) are now live on http://Kimi.ai, Kimi Work, Kimi Code, and the Kimi API.  
> 
> Open weights by Nov 4, 2026.
> 
> 🔗 API: http://platform.kimi.ai 
> 🔗 Tech blog: http://kimi.ai/blog/kimi-k3-1-pro

https://x.com/Kimi_Moonshot/status/2113680701770068067