Zhipu (GLM) · open weights · writing benchmark
GLM-5.2 sits at #45 of 130 on ToneBench, in the middle of the pack, with a writing Elo of 1764 and an overall score of 83.0 out of 100. We measured it by having it write all 9 of our real YouTube scripts, five times each, then scoring every draft blind against our own finished versions. Here is how it shook out.
Within Zhipu (GLM) it ranks 2nd of 5. GLM-5 is the family's top writer here, about 19 Elo ahead, so this config trades some quality for whatever it saves you in cost or speed.
Among open-weights models, it comes in 7th of 47. Open weights still trail the closed frontier on pure voice fidelity, and you can see that in the gap at the top.
What it does best is Hook: it ranks 37th on that dimension at 86.6, well above the board average. Its softer spot is Length Discipline (69.7, 71st), which is the thing to watch if that metric matters most for your use.
It was uneven across the 9 scripts. Its best run was the product release announcement / personal observation (85.5) and its weakest was the short explainer (79.4), a spread of about 6 points. Worth knowing if your writing skews toward one of those formats.
On cost, it runs about $0.022/task. DeepSeek V4 Flash 0731 scores higher for less money, at $0.005/task, so on pure value this config is not the frontier. Still, it beats 29 models that cost noticeably more.
The shape is the story: the further a corner reaches, the stronger that dimension. Biggest edge over the board: Visual Cues (+11.4); smallest edge: Length Discipline (+2.6).
Nine writing dimensions, each scored 0–100 and blended by the editorial weight shown. Rank is against all 130 current-ranked models. The thick bar is this model; the thin lines above and below are the current field's best model (darker) and average (lighter) on the same scale. The small ± number is its run-to-run variation.
The same 9 real scripts every current-ranked model writes, scored individually. Different formats stress different skills.
Every cell on this page is the mean of 5 independent runs per script; the ± numbers are the run-to-run standard deviation. Overall, GLM-5.2 varies by ± 2.8 points between runs versus a board median of ± 3.8, so it is noticeably steadier than the typical model here.
Its most volatile dimension is Length Discipline (± 15.5 vs a board median of ± 8.6): two runs of the same brief can land visibly different length discipline scores. Its steadiest is Hook (± 1.8 vs ± 3.0 board median), which you can rely on run after run.
| Metric | This model | Board median | Verdict |
|---|---|---|---|
| Tone & Voice ? | 85.3 ± 1.5 | ± 2.2 | typical |
| Writing Craft ? | 84.7 ± 1.8 | ± 2.0 | typical |
| Substance & Value ? | 85.0 ± 2.8 | ± 2.6 | typical |
| Flow & Emotion ? | 80.5 ± 2.4 | ± 2.6 | typical |
| YouTube Structure ? | 81.0 ± 3.1 | ± 3.6 | typical |
| Hook ? | 86.6 ± 1.8 | ± 3.0 | steadier than most |
| Length Discipline ? | 69.7 ± 15.5 | ± 8.6 | swingier than most |
| Anti-Slop ? | 87.4 ± 2.5 | ± 2.6 | typical |
| Visual Cues ? | 85.9 ± 2.9 | ± 4.7 | typical |
Numbers we log on every run and rarely talk about. None of these affect the writing scores; cost and latency are informational.
The published overall of 83.0 is the consensus of three family-disjoint judges scoring the same 45 stored drafts blind with the identical rubric. The highest and lowest judge differ by 7.1 points on its overall. A typical amount of judge disagreement for this board. How the panel works: methodology.
z-ai/glm-5.2 (provider default reasoning)z-ai/glm-5.2 for automated_video_workflow (Task-7 exact OpenRouter endpoint pin novita/fp8)On ToneBench it ranks #45 of 130 with a writing Elo of 1764 and an overall score of 83.0/100. That score comes from writing our 9 real YouTube scripts five times each and scoring every draft blind against our own finished versions across nine writing dimensions.
Not quite. Within Zhipu (GLM) it ranks 2nd of 5; GLM-5 is the family's best writer here.
It costs about $0.022/task. DeepSeek V4 Flash 0731 scores higher for less, so it is not the value pick.
Its strongest dimension is Hook (37th on the board, 86.6). Its weakest is Length Discipline (71st on the board, 69.7). The full nine-metric breakdown is on this page.
Yes. Its best of our 9 scripts was the product release announcement / personal observation (85.5) and its weakest was the short explainer (79.4).
We run every script 5 times. GLM-5.2's overall score varies by about ±2.8 points between runs, versus a board median of ±3.8. That makes it one of the steadier models we test. The full per-metric variability table is on this page.
Via OpenRouter using the exact model/route id z-ai/glm-5.2, run on 2026-07-29. 5 runs per script, provider-default sampling, no fine-tuning; every draft scored blind with a fixed rubric by a three-family judge panel. Full details in the 'How we ran it' section and the methodology.
Yes, it is an open-weights model. Among open-weights models it ranks 7th of 47 for writing.