Resolved This issue has been resolved. Impact occurred from 5:50pm PT / 00:50 UTC to 7:10pm PT / 02:10 UTC. Posted Sep 22 , 2026 - 02:35 UTC Monitoring We have seen success rates return to normal across affected models, and are monitoring closely to ensure no further issues. Posted Sep 22 , 2026 - 02:11 UTC Update 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. Posted Sep 22 , 2026 - 01:35 UTC 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. Posted Sep 22 , 2026 - 01:17 UTC Investigating We are investigating elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, and Claude Opus 5.…