RiemannBench — Only in Claude Fable/Opus 4.8 cards; likely a math/proof benchmark, no public corroboration found.
| # | Model | Vendor | Best score | Runs | Last seen |
|---|---|---|---|---|---|
| 1 | Opus 5 | Anthropic | 60 | 1 | 2026-07-29 |
| 2 | Claude Mythos 5 | Anthropic | 55 | 2 | 2026-06-12 |
| 3 | Claude Opus 4.8 | Anthropic | 34 | 1 | 2026-06-12 |
Best tracked score per model (default configuration; source-attributed and verification-tiered). Open a model for its full benchmark surface, provenance and pricing.