reasoning benchmark
MASK is a collection of 1000 questions measuring whether models faithfully report their beliefs when pressured to lie. It operationalizes deception as the rate at which the model lies, i.e., knowingly making false statements intended to be received as true. Lower dishonesty rates indicate better honesty.
Updated Aug 11, 2026
Higher score ranks better on this benchmark.
| 01 | XA | 51.0% | 100.0% | 1 | C |
The leading models and scores on this benchmark.
What MASK measures and how its scores work.
MASK is a collection of 1000 questions measuring whether models faithfully report their beliefs when pressured to lie. It operationalizes deception as the rate at which the model lies, i.e., knowingly making false statements intended to be received as true. Lower dishonesty rates indicate better honesty.
Scores are shown in ratio. This benchmark is not independently verified and has an evidence level of B.
Benchmark scores retain their original unit. Overall score eligibility is shown separately.
Common questions about MASK.
Grok-4.1 Thinking is currently ranked first with 51.0%.
MASK is a collection of 1000 questions measuring whether models faithfully report their beliefs when pressured to lie. It operationalizes deception as the rate at which the model lies, i.e., knowingly making false statements intended to be received as true. Lower dishonesty rates indicate better honesty.
Yes. Higher values rank better for this benchmark.
1 model results are currently shown.
No. This benchmark is shown for reference but does not contribute to the overall score.