GLM-5.1 is a flagship large language model designed with agentic engineering as its core purpose. Built on a 754-billion parameter architecture, it represents a deliberate shift away from models that burn bright on first attempts but then plateau. The design philosophy centers on sustained effectiveness across extended reasoning sessions, enabling the model to decompose complex software engineering problems, run iterative experiments, read and interpret results, and identify blockers with growing precision. Unlike its predecessors that tend to exhaust their initial repertoire quickly, GLM-5.1 is engineered to keep revising its approach and maintaining productive momentum over hundreds of reasoning rounds and thousands of tool invocations.
The model carries forward the GLM family lineage while marking a substantial leap in coding capability. It achieves state-of-the-art performance on SWE-Bench Pro, a benchmark for complex software engineering tasks, surpassing the results of GLM-5, GPT-5.4, and Gemini 3.1 Pro on this measure. On repository generation and real-world terminal tasks, GLM-5.1 leads its predecessor GLM-5 by a wide margin. The model is distributed under an MIT license as an open-weight release, making it accessible for both commercial and non-commercial applications. Its architecture supports adaptive problem-solving that can sustain autonomous execution for up to eight hours, positioning it as a practical choice for developers and enterprises seeking to automate extended engineering workflows without sacrificing quality or effectiveness.