Elevated errors for multiple models

Claude Status · Resolved

Status

Resolved

Severity

Unknown

Started

Sep 03, 2026 13:26 UTC

Resolved

Sep 03, 2026 16:23 UTC

Timeline

Resolved · Claude Status · Sep 03 16:23 UTC

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 →
Monitoring · Claude Status · Sep 03 16:06 UTC

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.

Elevated errors for multiple models →
Update · Claude Status · Sep 03 15:25 UTC

Update

The only affected models right now are Opus 4.8 and Opus 5. The rest of the models have recovered to baseline error rate.

Elevated errors for multiple models →
Update · Claude Status · Sep 03 14:49 UTC

Update

We are continuing to work on a fix for this issue.

Elevated errors for multiple models →
Update · Claude Status · Sep 03 13:50 UTC

Update

An exhaustive list of affected models: Mythos/Fable 5.1, Mythos/Fable 5, Opus 5, Opus 4.8, Opus 4.6.

Elevated errors for multiple models →
Identified · Claude Status · Sep 03 13:41 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.

Elevated errors for multiple models →
Investigating · Claude Status · Sep 03 13:26 UTC

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.

Elevated errors for multiple models →