Kimi K2 Thinking (Vertex AI (OpenAI-compatible))

Kimi K2 Thinking is an open-source thinking model positioned as a reasoning agent that interleaves step-by-step deliberation with tool use, aimed at long-horizon research, planning, and coding workflows. Moonshot AI describes it as built for test-time scaling, increasing both the number of thinking tokens and the depth of tool-calling steps so the model can stay coherent across extended task chains. The weights are released, which means teams can self-host the model or route traffic through compatible gateways in addition to using the hosted API.

The model's intended use is grounded in its agentic evaluation profile, where it reports state-of-the-art results on benchmarks that stress multi-step reasoning and tool use, including Humanity's Last Exam with tools, BrowseComp for agentic search, and SWE-Bench Verified for agentic coding. It can reportedly execute 200 to 300 sequential tool calls without human intervention, making it a fit for autonomous pipelines that need sustained planning, browsing, and code modification. For practitioners, the practical appeal is combining a large context window with strong tool-calling depth, which suits complex research assistants, automated debugging agents, and search-heavy analysis tasks that benefit from open-weight deployment.