Exciting news: @Kimi_Moonshot has released the open weights for Kimi K3.1 Pro, now #1 among open models in Agent Arena!

Across 17.5K+ real-world, long-horizon agentic sessions from our global community of users, Kimi K3.1 Pro (Max) delivers +5.1% net improvement, ranking #1 open and #13 overall.

It ranks #1 among open models in all three categories: Work, Code, and Chat.

This is a +4.2 percentage point improvement over Kimi K3 (Max), with +0.9% (#6 open). It also improved across all signals. Among open models, it ranks:
- #1 in Bash Reliability (successful shell commands) with +7.9%: (up from K3 at #13 with −4.5%).
- #1 in Praise vs Complaint (sentiment in user reactions) with +7.7%: (up from K3 at #6 with +1.3%).
- #1 in Steerability (responding to user corrections) with +6.5%: (up from K3 at #5 with +0.4%).
- #4 in Confirmed Success (explicit “yes, that worked” from users) with +3.9%: (from K3 at #5 with +3.8%).

Congrats to @Kimi_Moonshot on this contribution to the open ecosystem!