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AnthropicIncidentMateriality 2

Anthropic investigates elevated errors on Claude Mythos 5.1 and Fable 5.1

Anthropic is investigating elevated errors on requests to Claude Mythos 5.1 and Claude Fable 5.1. The incident is marked major and remains unresolved.

First seen 5 Oct, 13:05 UTC on status.claude.com2 sourcesLast update 1h ago

What the sources say

Linked, never rewritten. Official means the lab itself.

Official2

status.claude.com· 5 Oct, 13:05Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1status.claude.com· 5 Oct, 13:21Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1

Press0

No independent coverage yet.

How it unfolded

Every source in the order it appeared. Times in UTC.

5 Oct 13:05status.claude.com Elevated errors for Claude Mythos 5.1 and Claude Fable 5.15 Oct 13:21status.claude.com Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1

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