Outage in Claude
Elevated errors for multiple models
Resolved MajorIncident Report
Summary AI Generated
On September 3, 2026, Claude experienced elevated error rates lasting approximately 2.9 hours, affecting multiple models including Claude Mythos 5.1, Claude Fable 5.1, Opus 5, Opus 4.8, and Opus 4.6 across both claude.ai and the API. Users were unable to get responses, load files, or complete requests, with many experiencing indefinite loading states. A fix was deployed and the incident was fully resolved by 16:16 UTC.
We are investigating elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5. We will provide an update as soon as possible.
Components affected
Claude claude.ai Claude api.anthropic.comLatest Updates ( sorted recent to last )
RESOLVED
8 days ago - at 09/03/2026 04:23PM
The issue affecting Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5 has been resolved. Impact has ended as of 9:16 PT / 16:16 UTC.
MONITORING
8 days ago - at 09/03/2026 04:06PM
A fix has been deployed for Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5 and we are monitoring for recovery.
IDENTIFIED
8 days ago - at 09/03/2026 03:25PM
The only affected models right now are Opus 4.8 and Opus 5. The rest of the models have recovered to baseline error rate.
IDENTIFIED
8 days ago - at 09/03/2026 02:49PM
We are continuing to work on a fix for this issue.
IDENTIFIED
8 days ago - at 09/03/2026 01:50PM
An exhaustive list of affected models: Mythos/Fable 5.1, Mythos/Fable 5, Opus 5, Opus 4.8, Opus 4.6.
IDENTIFIED
8 days ago - at 09/03/2026 01:41PM
We have identified the cause of elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5 and are working on a fix. We will provide an update as soon as possible.
INVESTIGATING
8 days ago - at 09/03/2026 01:26PM
We are investigating elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5. We will provide an update as soon as possible.
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