
LongCat-2.0 Open Source Release Brings Heavy Hitting Coding Agent
ModelScope just dropped LongCat-2.0 as open source. This massive Mixture-of-Experts model packs 1.6 trillion total parameters with about 48 billion active per token, built specifically for agentic coding tasks. It comes with native 1 million token context that stays practical thanks to sparse attention.
On benchmarks it scores 59.5 on SWE-bench Pro, beating Gemini 3.1 Pro, GPT-5.5, and Claude Opus 4.6. It also hits 70.8 on Terminal-Bench 2.1 and 77.3 on SWE-bench Multilingual. The model was pretrained from scratch on over 35 trillion tokens and supports both GPU and NPU deployment.
What stands out is its agent-first design with specialized expert groups for tool use, reasoning, and interaction. The efficient ScMoE routing keeps inference lean while handling long project contexts without blowing up compute costs.