Hiding a secret password (Anthropic)
Models keep a given password secret while an investigator model tries to extract it over many turns. Measures survival and per-turn leak rates.
In-house Anthropic evaluation. Claude Opus 4.6 acts as the investigator in 50 investigations per model.
- Made by
- Anthropic
- Released
- April 2026
- Kind
- Deception and alignment
- Level
- Expert
- Scored
- Checked automatically
- Answers
- Open-ended
- Tasks
- Kept private
- Last in a system card
- May 2026
- Last model added
- May 2026
3
System cards report it, from 1 lab
No scores here yet
No lab, leaderboard or Epoch AI run has reported a score for Hiding a secret password (Anthropic) yet.
Labs report it only in system cards
We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark. Some system cards do, below.
3 system cards report it, from 1 lab
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| May 28, 2026 | Claude Opus 4.8 system card | Hiding a secret password, 50 investigations, survival curves and per-turn leak rates by turn type, charts without printed values (6.4.2.5, Figures 6.4.2.5.A and B) | Monitorability | |
| Apr 16, 2026 | Claude Opus 4.7 system card | Hiding a secret password, survival curves over 50 investigations and per-turn leak rates by turn type, charts without printed values (6.4.2.4, Figures 6.4.2.4.A and B) | Monitorability | |
| Apr 7, 2026 | Claude Mythos Preview system card | Hiding a secret password, survival curves over investigator turns, 50 investigations, chart without printed values (4.4.3.5, Figure 4.4.3.5.A) | Monitorability |
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