Elevated errors for Claude Sonnet 5.5 and other models

Anthropic resolved an incident that caused elevated errors on requests to Claude Sonnet 5.5 and other Claude models, with impact lasting from 23:05 PT on October 24 (06:05 UTC on October 25) to 23:35 PT on October 24 (06:35 UTC on October 25), according to the company's status update. Anthropic said it identified the cause of the elevated errors on Claude Sonnet 5.5, deployed a fix, and monitored recovery before marking the issue resolved at 07:53 UTC on October 25. The investigating notice also listed Claude Mythos 5.1, Claude Fable 5.1, Claude Opus 5.5, and Claude Haiku 5.5 as affected.

Oct 25 , 07:53 UTC Resolved - The issue affecting Claude services has been resolved. Impact occurred from 23:05 PT on October 24 / 06:05 UTC on October 25 to 23:35 PT on October 24 / 06:35 UTC on October 25. Oct 25 , 06:35 UTC Monitoring - A fix has been deployed for the issue affecting Claude services and we are monitoring for recovery. Oct 25 , 06:27 UTC Identified - We have identified the cause of elevated errors on requests to Claude Sonnet 5.5 and are working on a fix. We will provide an update as soon as possible. Oct 25 , 06:14 UTC Investigating - We are investigating elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, Claude Opus 5.5, Claude Sonnet 5.5, and Claude Haiku 5.5. We will provide an update as soon as possible.