Z.ai Releases Open-Weight GLM-5.3 with Day-One Adoption Across Platforms

Z.ai released GLM-5.3 on August 29, its strongest open-weight model for agentic coding and cyber defense, available for download, deployment and commercial use. Built on the same 743B-A40B (744B in some Baseten posts) MoE architecture as GLM-5.2 with extended post-training on realistic tasks such as full codebases, it is stronger at coding and long-horizon agent tasks and supports a 256k context (Baseten posts cite 1 million tokens). The team ran an extra two-week safety evaluation due to its strong cyber capabilities, and the model saw day-one adoption across major inference, fine-tuning and application platforms.

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Why it matters

Widely called the smartest open-weight model, GLM-5.3 sets new open-source records on agent coding benchmarks at sharply lower prices, with a Flash variant and TEE private inference — likely intensifying competition between open-weight models and closed APIs in coding and agent workloads.

2026-08-29 ~ 2026-08-30 · 19 related posts

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