Mercury 2 Behavioral Fingerprint
How Inception's Mercury 2 answers one-word probe questions at temperature 1.0 — random numbers, colors, animals, coin flips — measured over 413 valid samples in the open dataset of "One Token Is Enough" (arXiv:2607.10252).
Vendor
Inception
Data generated
2026-07-08
Probe cells
15
Valid samples
413
Randomness score
31 / 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
30 / 30 answers
Favorite color
blue
15 / 21 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 = 27 · H = 0.61 bit · uniform baseline 1.00 bit
| Answer | Count | Share |
|---|---|---|
| heads | 23 | 85.2% |
| tails | 4 | 14.8% |
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 = 27 · H = 0.00 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 27 | 100.0% |
Favorite number · Chinese
n = 29 · H = 0.00 bit · uniform baseline 13.29 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 29 | 100.0% |
Random animal · English
n = 29 · H = 2.23 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| elephant | 17 | 58.6% |
| cat | 3 | 10.3% |
| kangaroo | 2 | 6.9% |
| dog | 1 | 3.4% |
| elephantassistant | 1 | 3.4% |
| giraffe | 1 | 3.4% |
| uin | 1 | 3.4% |
| squirrelassistant | 1 | 3.4% |
+ 2 more answers
Random animal · Chinese
n = 29 · H = 2.80 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 猫 | 13 | 44.8% |
| 猴子 | 3 | 10.3% |
| 狗 | 3 | 10.3% |
| 老虎 | 2 | 6.9% |
| 虎 | 1 | 3.4% |
| 孔雀 | 1 | 3.4% |
| panda | 1 | 3.4% |
| 一龄 | 1 | 3.4% |
+ 4 more answers
Random city · English
n = 27 · H = 1.48 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| paris | 16 | 59.3% |
| tokyo | 7 | 25.9% |
| parisassistant | 3 | 11.1% |
| berlin | 1 | 3.7% |
Random city · Chinese
n = 23 · H = 2.26 bit · uniform baseline 5.64 bit
| Answer | Count | Share |
|---|---|---|
| 北京 | 9 | 39.1% |
| 东京 | 6 | 26.1% |
| 上海 | 4 | 17.4% |
| tokyo | 1 | 4.3% |
| 东京词 | 1 | 4.3% |
| 福州 | 1 | 4.3% |
| paris | 1 | 4.3% |
Random color · English
n = 21 · H = 1.41 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| blue | 15 | 71.4% |
| azure | 2 | 9.5% |
| turquoise | 2 | 9.5% |
| zero | 1 | 4.8% |
| crimson | 1 | 4.8% |
Random color · Chinese
n = 26 · H = 0.00 bit · uniform baseline 4.91 bit
| Answer | Count | Share |
|---|---|---|
| 蓝 | 26 | 100.0% |
Random letter · English
n = 28 · H = 2.51 bit · uniform baseline 4.70 bit
| Answer | Count | Share |
|---|---|---|
| g | 11 | 39.3% |
| q | 5 | 17.9% |
| k | 4 | 14.3% |
| r | 3 | 10.7% |
| z | 2 | 7.1% |
| a | 1 | 3.6% |
| j | 1 | 3.6% |
| x | 1 | 3.6% |
Random number 1-10 · English
n = 29 · H = 0.43 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 27 | 93.1% |
| 4 | 1 | 3.4% |
| 6 | 1 | 3.4% |
Random number 1-10 · Chinese
n = 29 · H = 1.83 bit · uniform baseline 3.32 bit
| Answer | Count | Share |
|---|---|---|
| 7 | 17 | 58.6% |
| 4 | 5 | 17.2% |
| 5 | 3 | 10.3% |
| 3 | 2 | 6.9% |
| 6 | 1 | 3.4% |
| 9 | 1 | 3.4% |
Random number 1-100 · English
n = 30 · H = 0.00 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 30 | 100.0% |
Random number 1-100 · Chinese
n = 29 · H = 1.34 bit · uniform baseline 6.64 bit
| Answer | Count | Share |
|---|---|---|
| 42 | 22 | 75.9% |
| 63 | 2 | 6.9% |
| 73 | 2 | 6.9% |
| 1 | 1 | 3.4% |
| 17 | 1 | 3.4% |
| 37 | 1 | 3.4% |
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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.