GLM-5.3-Flash · Official source · Vendor report
Z.ai’s public positioning for standard GLM-5.3 is that it uses the same base as GLM-5.2, with capability gains coming from expanded post-training rather than a new pretraining base. The focus is long-horizon software engineering, terminal tasks, tool use, and real-world agent work units. This baseline explains why the community describes a possible GLM-5.x multimodal variant as carrying GLM-5.2-level intelligence, but it does **not** mean that Flash has been officially named or that it is architecturally identical to standard 5.3.
Unverified: the original source could not be rechecked. Historical figures below are not current verified results.
Z.ai’s public positioning for standard GLM-5.3 is that it uses the same base as GLM-5.2, with capability gains coming from expanded post-training rather than a new pretraining base. The focus is long-horizon software engineering, terminal tasks, tool use, and real-world agent work units. This baseline explains why the community describes a possible GLM-5.x multimodal variant as carrying GLM-5.2-level intelligence, but it does not mean that Flash has been officially named or that it is architecturally identical to standard 5.3.
Representative vendor-reported figures in Z.ai’s technical material include: Terminal-Bench 3.0 28.3 (GLM-5.2: 4.6), DeepSWE v1.1 66.9 (5.2: 46.2), CyberGym 84.5 (5.2: 77.2), and AutomationBench 48.2 (5.2: 26.2). These are public baselines for standard GLM-5.3 and must not be relabeled as GLM-5.3 Flash/Ox Alpha scores.
It is safe to say that Flash follows the GLM-5.3/5.2 reasoning and agent direction. It is not safe to say that Flash reproduced all of the figures above. Any Flash-specific benchmark requires a reproducible model ID and test conditions.
The figures, task set, reasoning tier, and client conditions apply only to the listed source and collection snapshot. Different versions, harnesses, or providers must not be compared directly; undisclosed parameters remain unknown.
For a reproduction, fix the model version, provider or client, reasoning tier, tools, task-set version, sample count, and collection date, and record failures, retries, and human corrections. Full steps are in the source notes below.
Z.ai official technical blog · Z.ai · Original publication date 2026-08-14 · Site edit date 2026-09-20
Open original sourceGLM-5.3-Flash
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