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Claude (Anthropic) · 3d ago

Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1

Resolved

Timeline

Started: Sep 11, 2026, 2:19 PM UTC

Last update: Sep 11, 2026, 2:37 PM UTC

Resolved: Sep 11, 2026, 2:37 PM UTC

Affected: rwppv331jlwc, k8w3r06qmzrp, yyzkbfz2thpt, bpp5gb3hpjcl

Claude (Anthropic)'s official report →

Updates

  • resolved

    The issue affecting Claude services has been resolved. Impact occurred from 13:57 to 14:20 UTC

    Sep 11, 2026, 2:37 PM UTC

  • monitoring

    A fix has been deployed for the issue affecting Claude services and we are monitoring for recovery.

    Sep 11, 2026, 2:28 PM UTC

  • monitoring

    A fix has been deployed for Claude Mythos 5.1 and Claude Fable 5.1 and we are monitoring for recovery.

    Sep 11, 2026, 2:28 PM UTC

  • identified

    We have identified the cause of elevated errors on requests to Claude Mythos 5.1 and Claude Fable 5.1 and are working on a fix. We will provide an update as soon as possible.

    Sep 11, 2026, 2:21 PM UTC

  • investigating

    We are investigating elevated errors on requests to Claude Fable 5.1 and Claude Mythos 5.1. We will provide an update as soon as possible.

    Sep 11, 2026, 2:19 PM UTC

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