Moonshot AI has released Kimi K3, an open-source AI model boasting 2.8 trillion parameters. This release positions it as the world's largest open-source AI model and a significant contender against proprietary systems. Kimi K3 features a 1-million-token context window and native visual understanding capabilities. Its architecture incorporates Kimi Delta Attention and Attention Residuals, developed internally by Moonshot AI. The model demonstrates performance comparable to leading proprietary models like Claude and GPT on various benchmarks. Notably, Kimi K3 achieved a state-of-the-art score on the BrowseComp benchmark. The company also showcased K3's autonomous agent capabilities through a 48-hour chip design demonstration. This impressive feat highlights the model's ability to sustain complex, multi-step technical work. The release of Kimi K3 marks a major advancement for the open-source AI movement, potentially closing the performance gap with closed-source alternatives. This strategic move allows companies to fine-tune and self-host powerful AI systems without relying on external API contracts.