resolved
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.
Elevated errors for multiple models
Official Claude incident record with affected components, status, timeline updates, and links back to relevant status checks.
Affected components
These are the official Claude components attached to this incident. Component data can help separate a web app issue from an API, Console, or Claude Code issue.
claude.aiClaude API (api.anthropic.com)Claude CodeClaude Cowork
Official timeline
Updates are shown from the official Claude status incident record.
monitoring
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
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
We are continuing to work on a fix for this issue.
identified
An exhaustive list of affected models: Mythos/Fable 5.1, Mythos/Fable 5, Opus 5, Opus 4.8, Opus 4.6.
identified
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
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.