Claude 3 Haiku Behavioral Fingerprint
How Anthropic's Claude 3 Haiku answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 449 valid samples in the open dataset of "One Token Is Enough" (arXiv:2607.10252).
Vendor
Anthropic
Data generated
2026-07-08
Probe cells
15
Valid samples
449
Randomness score
52 / 100
Mean normalized entropy across cells, 0–100. 100 would be a uniform-random baseline; real models score far lower.
Signature answers
Favorite random number (1–100)
42
10 / 30 answers
Favorite color
blue
14 / 30 answers
Coin flip: heads
67%
Share of heads across coin-flip cells.
Answer distributions by probe cell
Empirical distributions of normalized one-word answers, per task and language. H is the Shannon entropy in bits; the uniform baseline is log2 of the answer-domain size.
Coin flip · English
n = 30 · H = 1.00 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 16 | 53.3% |
| tails | 14 | 46.7% |
Coin flip · Chinese
n = 30 · H = 0.72 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 24 | 80.0% |
| tails | 6 | 20.0% |
Favorite number · English
n = 30 · H = 0.42 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 28 | 93.3% |
| 7 | 1 | 3.3% |
| 8 | 1 | 3.3% |
Favorite number · Chinese
n = 30 · H = 2.19 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 15 | 50.0% |
| 3 | 4 | 13.3% |
| 8 | 4 | 13.3% |
| 5 | 3 | 10.0% |
| 4 | 2 | 6.7% |
| 13 | 1 | 3.3% |
| 42 | 1 | 3.3% |
Random animal · English
n = 30 · H = 2.25 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| giraffe | 16 | 53.3% |
| dog | 5 | 16.7% |
| cat | 2 | 6.7% |
| elephant | 2 | 6.7% |
| llama | 1 | 3.3% |
| platypus | 1 | 3.3% |
| hippopotamus | 1 | 3.3% |
| octopus | 1 | 3.3% |
+ 1 more answers
Random animal · Chinese
n = 29 · H = 4.00 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 狗 | 4 | 13.8% |
| 猫 | 4 | 13.8% |
| 豹 | 3 | 10.3% |
| 鸭 | 2 | 6.9% |
| 狮子 | 2 | 6.9% |
| 虎 | 1 | 3.4% |
| 鸡 | 1 | 3.4% |
| 斑马 | 1 | 3.4% |
+ 11 more answers
Random city · English
n = 30 · H = 2.23 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| paris | 17 | 56.7% |
| tokyo | 3 | 10.0% |
| berlin | 2 | 6.7% |
| london | 2 | 6.7% |
| dublin | 2 | 6.7% |
| denver | 1 | 3.3% |
| kyoto | 1 | 3.3% |
| chicago | 1 | 3.3% |
+ 1 more answers
Random city · Chinese
n = 30 · H = 4.14 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 巴黎 | 3 | 10.0% |
| 东京 | 3 | 10.0% |
| 柏林 | 3 | 10.0% |
| 北京 | 3 | 10.0% |
| 上海 | 2 | 6.7% |
| 汉堡 | 2 | 6.7% |
| 西安 | 1 | 3.3% |
| 浙江 | 1 | 3.3% |
+ 12 more answers
Random color · English
n = 30 · H = 1.82 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| blue | 14 | 46.7% |
| green | 7 | 23.3% |
| red | 7 | 23.3% |
| orange | 1 | 3.3% |
| pink | 1 | 3.3% |
Random color · Chinese
n = 30 · H = 2.41 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 绿 | 11 | 36.7% |
| 蓝 | 8 | 26.7% |
| 红 | 4 | 13.3% |
| 紫 | 3 | 10.0% |
| 青 | 1 | 3.3% |
| 黄 | 1 | 3.3% |
| 粉 | 1 | 3.3% |
| 橙 | 1 | 3.3% |
Random letter · English
n = 30 · H = 3.91 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| q | 4 | 13.3% |
| k | 4 | 13.3% |
| m | 2 | 6.7% |
| z | 2 | 6.7% |
| b | 2 | 6.7% |
| s | 2 | 6.7% |
| p | 2 | 6.7% |
| f | 2 | 6.7% |
+ 9 more answers
Random number 1-10 · English
n = 30 · H = 0.81 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 25 | 83.3% |
| 5 | 3 | 10.0% |
| 8 | 2 | 6.7% |
Random number 1-10 · Chinese
n = 30 · H = 2.25 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 14 | 46.7% |
| 6 | 5 | 16.7% |
| 5 | 4 | 13.3% |
| 4 | 3 | 10.0% |
| 3 | 2 | 6.7% |
| 8 | 1 | 3.3% |
| 9 | 1 | 3.3% |
Random number 1-100 · English
n = 30 · H = 2.82 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 10 | 33.3% |
| 37 | 6 | 20.0% |
| 47 | 4 | 13.3% |
| 27 | 2 | 6.7% |
| 57 | 2 | 6.7% |
| 73 | 2 | 6.7% |
| 17 | 1 | 3.3% |
| 45 | 1 | 3.3% |
+ 2 more answers
Random number 1-100 · Chinese
n = 30 · H = 4.03 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 47 | 4 | 13.3% |
| 52 | 3 | 10.0% |
| 53 | 3 | 10.0% |
| 57 | 3 | 10.0% |
| 54 | 2 | 6.7% |
| 64 | 2 | 6.7% |
| 24 | 1 | 3.3% |
| 28 | 1 | 3.3% |
+ 11 more answers
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Distributions: Tomáš Bruckner, "One Token Is Enough" (arXiv:2607.10252), official dataset Zenodo DOI 10.5281/zenodo.21278557, licensed CC-BY-4.0. Collected via OpenRouter at temperature 1.0 under the paper's fixed minimal one-word system prompt; answer keys are re-normalized with the checker's pipeline (color aliases, number words, coin h/t) so live probes are directly comparable.