Moonshot AI
Kimi
Beijing-based lab founded by ex-Tsinghua researchers. Kimi K1.5 and K2 push very long context and reasoning; K2 is a trillion-parameter MoE with strong tool-use behaviour.
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Moonshot AI is a Beijing-based lab founded by researchers from Tsinghua. Its Kimi Chat consumer product broke into the top of the Chinese-language LLM market in 2024 by offering a very long context window; the Kimi Chat backend ran on models the lab has since started opening.
Kimi K1.5 (early 2025) was Moonshot's first public reasoning-focused release, followed by Kimi K2 in mid-2025. K2 is a trillion-parameter mixture-of-experts (32B active per token), trained on 15.5T tokens, and is one of the most capable openly-available reasoning + agent models.
The K2 licence is a modified MIT with an attribution requirement for very-large deployments (100M MAU or $20M monthly revenue). For all typical use, this is effectively permissive.