# Kimi K3.1 Pro nears Opus 5.5 on Terminal-Bench 4.0 at half the cost

> Original title: Kimi K3.1 Pro nearly matches Opus 5.5 performance on Terminal-Bench 4.0 at *half* the cost.

- Source: Cline
- Published: 2026-10-23T17:40:52.000Z
- Bad Influence: https://badinfluence.news/items/rxqnsxqqt8o2rx1kp175uwmi2
- Original: https://x.com/cline/status/2113687112658882828

## Summary

Cline says Moonshot's Kimi K3.1 Pro nearly matches Opus 5.5 on Terminal-Bench 4.0 at half the cost. Moonshot also removed cyber data from mid-training and reinforcement learning, reducing performance on exploit tasks by about 10% while coding and other capabilities kept improving.

## Post

Kimi K3.1 Pro nearly matches Opus 5.5 performance on Terminal-Bench 4.0 at *half* the cost.

Moonshot also removed cyber data from mid-training and RL to deliberately reduce performance on exploit tasks by ~10%, while everything else, including coding, kept improving.

![](https://badinfluence.news/api/img-proxy?u=https%3A%2F%2Fpbs.twimg.com%2Fmedia%2FHVVSRuua4AAHsCm.jpg&mode=thumb&exp=1793836800&sig=e11436d04e32f704)