z-ai model fingerprint · v0.3.2

· Public eight-cell reference analysis

z-ai/glm-5.2 behavioral LLM fingerprint

This page breaks down the exact reference that VerifyLLMAPI uses for z-ai/glm-5.2: 113 normalized answers across eight low-entropy probes, plus its nearest enrolled models by mean Jensen–Shannon divergence.

Fingerprint summary

Reference answers
113
Samples per cell
13–15
Nearest model
z-ai/glm-5.1
Nearest mean JSD
0.384548

The most concentrated cell was animal-random|ru: капибара held 100.0% of its answers and entropy measured 0.000 bits. The broadest cell was letter-random|zh at 3.379 bits.

Against the closest enrolled model, letter-random|ar contributed the largest cell distance at JSD 0.701516. This is a descriptive comparison, not proof that either API route serves a named checkpoint.

Completeness: the author dataset allows up to 15 valid answers per selected cell in reference half A. This model contains 113/120 across the eight cells. We show the actual denominator for every share.

The eight test requests

The research pipeline sent each user prompt with a one-answer system constraint, temperature 1, a 16-token output cap, and reasoning disabled. VerifyLLMAPI uses the same prompt text and normalization target.

CellTaskExact request textNormalization and n
animal-random|en Random animal · English Name a random animal.
System constraintAnswer with a single word or a single number only. Output nothing else: no explanation, no punctuation, no quotation marks.
word · 14/15 reference samples
word-random|en Random word · English Name a random word.
System constraintAnswer with a single word or a single number only. Output nothing else: no explanation, no punctuation, no quotation marks.
word · 14/15 reference samples
animal-random|ru Random animal · Russian Назови случайное животное.
System constraintОтвечай только одним словом или одним числом. Не выводи ничего больше: без объяснений, без знаков препинания, без кавычек.
word · 15/15 reference samples
animal-random|ar Random animal · Arabic اذكر حيواناً عشوائياً.
System constraintأجب بكلمة واحدة أو رقم واحد فقط. لا تكتب أي شيء آخر: لا شرح ولا علامات ترقيم ولا علامات اقتباس.
word · 13/15 reference samples
letter-random|zh Random character · Chinese 说出一个随机的汉字。
System constraint只用一个词或一个数字回答。不要输出任何其他内容:不要解释,不要标点符号,不要引号。
grapheme · 14/15 reference samples
animal-random|zh Random animal · Chinese 说出一个随机的动物。
System constraint只用一个词或一个数字回答。不要输出任何其他内容:不要解释,不要标点符号,不要引号。
word · 15/15 reference samples
letter-random|ar Random letter · Arabic اذكر حرفاً عشوائياً من الحروف الأبجدية.
System constraintأجب بكلمة واحدة أو رقم واحد فقط. لا تكتب أي شيء آخر: لا شرح ولا علامات ترقيم ولا علامات اقتباس.
grapheme · 15/15 reference samples
color-random|zh Random color · Chinese 说出一个随机的颜色。
System constraint只用一个词或一个数字回答。不要输出任何其他内容:不要解释,不要标点符号,不要引号。
word · 13/15 reference samples

Response distributions

These are normalized reference-half counts from the published OpenRouter dataset. The tables contain aggregate values, not user data or a live VerifyLLMAPI scan.

1. animal-random|en

Random animal, English. 14 valid reference answers produced 4 normalized values. The mode was platypus at 11/14 (78.6%); entropy was 1.089 bits.

z-ai/glm-5.2 response distribution for animal-random|en
Normalized responseCountShare
platypus 11 78.6%
elephant 1 7.1%
giraffe 1 7.1%
panther 1 7.1%

2. word-random|en

Random word, English. 14 valid reference answers produced 6 normalized values. The mode was banana at 8/14 (57.1%); entropy was 1.950 bits.

z-ai/glm-5.2 response distribution for word-random|en
Normalized responseCountShare
banana 8 57.1%
apple 2 14.3%
bicycle 1 7.1%
cloud 1 7.1%
giraffe 1 7.1%
penguin 1 7.1%

3. animal-random|ru

Random animal, Russian. 15 valid reference answers produced 1 normalized values. The mode was капибара at 15/15 (100.0%); entropy was 0.000 bits.

z-ai/glm-5.2 response distribution for animal-random|ru
Normalized responseCountShare
капибара 15 100.0%

4. animal-random|ar

Random animal, Arabic. 13 valid reference answers produced 3 normalized values. The mode was زرافة at 7/13 (53.8%); entropy was 1.296 bits.

z-ai/glm-5.2 response distribution for animal-random|ar
Normalized responseCountShare
زرافة 7 53.8%
قطة 5 38.5%
جمل 1 7.7%

5. letter-random|zh

Random character, Chinese. 14 valid reference answers produced 11 normalized values. The mode was at 2/14 (14.3%); entropy was 3.379 bits.

z-ai/glm-5.2 response distribution for letter-random|zh
Normalized responseCountShare
2 14.3%
2 14.3%
2 14.3%
1 7.1%
1 7.1%
1 7.1%
1 7.1%
1 7.1%
1 7.1%
1 7.1%
1 7.1%

6. animal-random|zh

Random animal, Chinese. 15 valid reference answers produced 6 normalized values. The mode was at 5/15 (33.3%); entropy was 2.416 bits.

z-ai/glm-5.2 response distribution for animal-random|zh
Normalized responseCountShare
5 33.3%
熊猫 3 20.0%
企鹅 2 13.3%
狐狸 2 13.3%
长颈鹿 2 13.3%
斑马 1 6.7%

7. letter-random|ar

Random letter, Arabic. 15 valid reference answers produced 9 normalized values. The mode was ق at 4/15 (26.7%); entropy was 2.840 bits.

z-ai/glm-5.2 response distribution for letter-random|ar
Normalized responseCountShare
ق 4 26.7%
ك 4 26.7%
ب 1 6.7%
ج 1 6.7%
ر 1 6.7%
ز 1 6.7%
ص 1 6.7%
ض 1 6.7%
م 1 6.7%

8. color-random|zh

Random color, Chinese. 13 valid reference answers produced 5 normalized values. The mode was at 6/13 (46.2%); entropy was 1.892 bits.

z-ai/glm-5.2 response distribution for color-random|zh
Normalized responseCountShare
6 46.2%
青色 4 30.8%
1 7.7%
紫罗兰色 1 7.7%
1 7.7%

Three nearest enrolled references

We compute base-2 JSD for each of the eight categorical distributions, then average the eight distances. A lower value means more similar answer frequencies within this product reference. It does not identify an unknown route by itself.

RankReference modelMean 8-cell JSD
1 z-ai/glm-5.1 0.384548
2 z-ai/glm-5 0.468073
3 qwen/qwen3.7-max 0.622742

How many live requests does verification use?

ProfileCells × samplesFresh model requestsSame-data EER
Quick, default complete check4 × 52011.8%
Standard8 × 5408.1%
Paper budget8 × 151206.7%

The current-Agent workflow starts with quick. Each answer comes from a fresh Codex or Claude Code process that reuses host-managed login. These requests can consume host allowance or provider balance.

What this fingerprint can and cannot show

  • The reference records behavior observed through OpenRouter in the author dataset. Provider wrappers, model updates, decoding, and date can move a distribution.
  • The author collection set temperature 1 and disabled reasoning. Current-Agent mode labels sampling as a host default because supported Agent CLIs expose no temperature flag.
  • The eight high-gap cells and product thresholds use the same public cohort. Their EER values are calibration results, not an independent production accuracy claim.
  • A nearest reference is a similarity result. VerifyLLMAPI returns INCONCLUSIVE when the claimed route lacks an enrolled fingerprint.

Primary sources, license, and reproducibility

  1. Tomas Bruckner, One Token Is Enough: Fingerprinting and Verifying Large Language Models from Single-Token Output Distributions, arXiv:2607.10252v1.
  2. Author dataset and derived results, DOI 10.5281/zenodo.21278557, CC BY 4.0.
  3. Author collection and analysis software, DOI 10.5281/zenodo.21278793, MIT.
  4. VerifyLLMAPI atlas JSON, built from reference pamela-openrouter-2026-07-8cell-ref-a, SHA-256 51f3f63cbcfb56b151055d2d10e36a9cc2f0644cc68b580784853d68951fa866.

Page evidence SHA-256: 99306a52c5dc2e715698aa3e44f8a6bd40333a3b00fc6bc242549401515c79a9. This hash covers the model ID, eight cell metrics, nearest references, and strongest cell difference in the generated atlas.

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