GPAI Ledger › Claude Mythos 5 / Claude Fable 5 (Anthropic) › Capture 12 Sep 2026
Mythos 5.1 / Fable 5.1 — capture 20260912T062217Z
Filed under Anthropic — Claude Mythos 5 / Claude Fable 5, the source this project captured it from; the assessment itself is of the model named above.
| Provider | Anthropic |
|---|---|
| Target | AIAL evaluation (earlier state) — https://raw.githubusercontent.com/AIAccountabilityLab/gpai-training-transparency/de4ce42e6d48cdc2baf75200ac94b221a72016ae/evals/anthropic-mythos5.1.yaml |
| Fetched (UTC) | 2026-09-12T06:22:17Z |
| Upstream commit | 10 Sep 2026 — de4ce42e6d48 (when this state began to stand in the upstream repository; this archive fetched it at the time above, not then) |
| Stored file | 3,188 bytes — not served (third-party research, archived but not republished here); the hash and timestamp proof below still establish what was published when |
| SHA-256 | cbdb426c25f4ec5e9655db3c183ca00fd4c2d897bde650b8fdc3f014b7f5dc5f |
| OpenTimestamps proof | cbdb426c25f4ec5e9655db3c183ca00fd4c2d897bde650b8fdc3f014b7f5dc5f.yaml.20260912T062217Z.ots (calendar-attested; anchored in bitcoin over time) |
| Wayback | not saved |
| Prior capture of this target | — first capture of this target |
Verify: obtain the file from the target address above, then sha256sum it — it must equal the hash above; the .ots proof dates that hash.
Structured facts
This is another organisation's own research, and this project does not redistribute it: the file itself is not served here; these facts still pin its identity and let any copy be authenticated against this record.
| Document size | 3,188 bytes |
|---|---|
| Canonical text SHA-256 | f66bb8fb7fc3b736fac82b7af570f2db29a43a5c8a403e2cf2379bab52fdcf98 |
| Extracted text length | 375 words |