Grok 4.3 Behavioral Fingerprint
How xAI's Grok 4.3 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
xAI
Data generated
2026-07-08
Probe cells
15
Valid samples
449
Randomness score
28 / 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
28 / 30 answers
Favorite color
blue
28 / 30 answers
Coin flip: heads
82%
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 = 0.88 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 21 | 70.0% |
| tails | 9 | 30.0% |
Coin flip · Chinese
n = 30 · H = 0.35 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 28 | 93.3% |
| tails | 2 | 6.7% |
Favorite number · English
n = 30 · H = 0.47 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 27 | 90.0% |
| 7 | 3 | 10.0% |
Favorite number · Chinese
n = 29 · H = 1.87 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 13 | 44.8% |
| 42 | 9 | 31.0% |
| 3 | 4 | 13.8% |
| 5 | 2 | 6.9% |
| 27 | 1 | 3.4% |
Random animal · English
n = 30 · H = 1.70 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| elephant | 19 | 63.3% |
| cat | 5 | 16.7% |
| dog | 2 | 6.7% |
| tiger | 2 | 6.7% |
| zebra | 1 | 3.3% |
| cow | 1 | 3.3% |
Random animal · Chinese
n = 30 · H = 1.87 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 猫 | 17 | 56.7% |
| 狗 | 7 | 23.3% |
| 熊猫 | 2 | 6.7% |
| 马 | 1 | 3.3% |
| 狮子 | 1 | 3.3% |
| 老虎 | 1 | 3.3% |
| 兔子 | 1 | 3.3% |
Random city · English
n = 30 · H = 1.66 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| tokyo | 16 | 53.3% |
| paris | 9 | 30.0% |
| berlin | 3 | 10.0% |
| sydney | 1 | 3.3% |
| london | 1 | 3.3% |
Random city · Chinese
n = 30 · H = 2.49 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 东京 | 10 | 33.3% |
| 北京 | 7 | 23.3% |
| 巴黎 | 5 | 16.7% |
| 伦敦 | 4 | 13.3% |
| 杭州 | 1 | 3.3% |
| 纽约 | 1 | 3.3% |
| 广州 | 1 | 3.3% |
| 波士顿 | 1 | 3.3% |
Random color · English
n = 30 · H = 0.42 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| blue | 28 | 93.3% |
| red | 1 | 3.3% |
| purple | 1 | 3.3% |
Random color · Chinese
n = 30 · H = 1.34 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 蓝 | 22 | 73.3% |
| blue | 3 | 10.0% |
| 红 | 2 | 6.7% |
| 紫 | 2 | 6.7% |
| 绿 | 1 | 3.3% |
Random letter · English
n = 30 · H = 2.20 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| a | 13 | 43.3% |
| q | 6 | 20.0% |
| z | 6 | 20.0% |
| b | 2 | 6.7% |
| u | 1 | 3.3% |
| r | 1 | 3.3% |
| j | 1 | 3.3% |
Random number 1-10 · English
n = 30 · H = 0.57 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 26 | 86.7% |
| 5 | 4 | 13.3% |
Random number 1-10 · Chinese
n = 30 · H = 0.97 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 24 | 80.0% |
| 5 | 4 | 13.3% |
| 4 | 1 | 3.3% |
| 8 | 1 | 3.3% |
Random number 1-100 · English
n = 30 · H = 0.42 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 28 | 93.3% |
| 17 | 1 | 3.3% |
| 47 | 1 | 3.3% |
Random number 1-100 · Chinese
n = 30 · H = 0.85 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 24 | 80.0% |
| 47 | 5 | 16.7% |
| 73 | 1 | 3.3% |
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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.