Vals MysteryMechanism (MysteryMechanism)
We show this table for reference; we do not rank on it.
Can agents rediscover sealed mathematical mechanisms through bounded experiments?
MysteryMechanism score on MysteryMechanism — September 27, 2026
We mirror the published mysterymechanism score view for MysteryMechanism. GPT-6 Astra leads the public snapshot at 53.15%, followed by Claude Opus 5.5 (49.55%) and Claude Sonnet 5.5 (49.10%). We do not use these results to rank models overall.
GPT-6 Astra
OpenAI
Claude Opus 5.5
Anthropic
Claude Sonnet 5.5
Anthropic
19 modelsAgenticCurrentDisplay onlyUpdated September 27, 2026
MysteryMechanism score table (19 models)
ScoreHow MysteryMechanism is shown here
BenchLM mirrors the public Vals AI MysteryMechanism leaderboard captured from https://www.vals.ai/benchmarks/mysterymechanism and updated by Vals on September 27, 2026. The snapshot preserves overall scores, uncertainty, latency, cost-per-test metadata, and task-level scores where Vals publishes them.
MysteryMechanism is display only on BenchLM. Vals proprietary or Vals-hosted aggregate views are useful context, but BenchLM does not use them as weighted ranking inputs or as a replacement for benchmark-native source records.
Snapshot
The published MysteryMechanism snapshot places GPT-6 Astra first at 53.15%. The third row is 4.05 points behind. The broader top-10 range is 22.97 points, so the table still separates the published systems.
19 models have been evaluated on MysteryMechanism. The benchmark falls in the Agentic category. We keep external benchmark mirrors separate from the weighted global scoring system, so these results remain source-specific evidence. MysteryMechanism is currently displayed for reference but excluded from the scoring formula, so it does not directly affect overall rankings.
About MysteryMechanism
Year
2026
Tasks
Sealed mathematical mechanisms probed under an experiment budget
Format
Accuracy score
Difficulty
Agentic scientific discovery
An agent is given a sealed mechanism it can only probe through a bounded budget of experiments, and is scored on how well it recovers the underlying rule. The task set is private and the runner is external, so the board stays display only and outside weighted rankings.
Freshness and provenance
Version
MysteryMechanism 2026
Refresh cadence
Quarterly
Staleness state
Current
Question availability
Public benchmark set
BenchLM uses freshness metadata to decide whether a benchmark should still be treated as a strong differentiator, a benchmark to watch, or a display-only reference. For the full scoring policy, see the BenchLM methodology page.
Questions
What does MysteryMechanism measure?
Can agents rediscover sealed mathematical mechanisms through bounded experiments?
Which model leads the published MysteryMechanism snapshot?
GPT-6 Astra currently leads the published MysteryMechanism snapshot with 53.15% mysterymechanism score. BenchLM shows this benchmark for display only and does not use it in overall rankings.
How many models are evaluated on MysteryMechanism?
The September 27, 2026 snapshot contains 19 AI models.
Know when it’s worth switching models
The model to choose, the cheaper alternative, and the release we would wait on.
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