GLM-5.3 open-sourced with 1M context window, vLLM integration available

AccBalanced · x · 2026-08-29

Zai released the open weights for GLM-5.3, the most capable model in the GLM-5 series. It features a 743B-parameter MoE architecture (39B active), a 1M-token context window, and 128K max output. vLLM announced day-0 support, allowing deployment via vllm serve zai-org/GLM-5.3 -tp 8. The model defaults to native FP8 weights, fitting on a single node of 8xH200 or 8xH20, while maintaining compatibility with GLM-5.2 parsers and tool-calling paths.

Related event: Z.ai Open-Sources GLM-5.3, Touting Agentic Coding and Cyber Defense(9 posts)→

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