GLM-5.3-Flash is a 320B-parameter sparse model with 18B activated parameters, designed as the first natively multimodal entry in the GLM-5 series. The architecture introduces a hybrid combination of sparse and linear attention—the first such design in the GLM lineage—intended to cut long-context serving costs while preserving precision over extended inputs. An additional layer, Manifold-Constrained Hyper-Connections (mHC), is applied to improve scaling efficiency, and the model is pre-trained on a 30T-token multimodal corpus. Together these choices aim to deliver stronger capability from substantially less compute than the preceding GLM-5 generation.
On coding and agentic benchmarks, GLM-5.3-Flash posts Terminal-Bench 2.1 at 84.3, DeepSWE at 63.4, and Humanity's Last Exam at 55.3, with further results on Agent's Last Exam (26.3), AutomationBench v1.0.6 (48.8), and GDPval-AA v2 (1773) noted in the model card though not yet registered on the Hub. The model approaches Claude Opus 4.8 on several coding and agentic evaluations while improving clearly over GLM-5.2 on workloads such as DeepSWE v1.1 and AutomationBench. Its native multimodal design extends to visual coding and document understanding tasks, including slide layout verification and professional artifact interpretation. Open weights are published on Hugging Face under the zai-org organization, supporting local deployment with frameworks such as SGLang, vLLM, and TokenSpeed.