It was, perhaps, the worst-kept secret in the AI community. In mid-July, online sleuths who obsessively track the internet for signs of new AI models started to whisper about the latest offering from Moonshot AI, the Beijing-based artificial intelligence startup behind the Kimi large language model: Something big was coming. Moonshot AI’s latest model didn’t just live up to the hype—it raised the stakes. On July 16, Moonshot debuted Kimi K3, the largest open-source model ever released, and promised it could perform close to the level of Anthropic’s Fable 5—perhaps the most powerful publicly available model on the market today—at...