Kimi K3 is an open-weight multimodal model positioned by Moonshot AI as the first open 3T-class system, designed for frontier work in long-horizon coding, knowledge tasks, and reasoning. Its architecture introduces Kimi Delta Attention combined with Attention Residuals, scaling mixture-of-experts sparsity through a Stable LatentMoE framework that activates 16 out of 896 experts within a 2.8-trillion-parameter model. This blend of a new attention design and aggressive MoE sparsity gives the model capacity for broad knowledge while keeping inference efficient enough for practical agentic use, and native vision support allows image and video inputs to be processed alongside text without separate encoders.

With a 1-million-token context window and built-in tool calling plus structured output, Kimi K3 fits workflows that need sustained reasoning across very long documents, multi-step agent loops, and structured data exchange. Moonshot describes its overall performance as trailing the strongest proprietary systems while still reaching frontier levels on their evaluation suite, and its open release on Hugging Face makes it attractive for teams that want to self-host a top-tier model for research assistants, code agents, and document-heavy knowledge tasks without being tied to a closed API.