Elevated errors for multiple models

Event timeline

How this incident unfolded, from the official status page.

1. Investigating

   about 1 month ago

   Anthropic

   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.

2. Identified

   about 1 month ago

   Anthropic

   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.

3. Identified

   about 1 month ago

   Anthropic

   We are continuing to work to resolve errors affecting some models. At this time, requests to Claude Fable 5 and 5.1 and Mythos 5 and 5.1 have returned to normal success rates. We are working to resolve remaining errors affecting Claude Opus 5, and will provide an additional update shortly.

4. Monitoring

   about 1 month ago

   Anthropic

   We have seen success rates return to normal across affected models, and are monitoring closely to ensure no further issues.

5. Resolved

   about 1 month ago

   Anthropic

   This issue has been resolved. Impact occurred from 5:50pm PT / 00:50 UTC to 7:10pm PT / 02:10 UTC.