major✓ Resolved

Intermittent error spikes for Claude Mythos 5.1 and Claude Fable 5.1

Anthropic (Claude)•2026-09-15 09:48 UTC

Status

resolved

Duration

1h 26m

Updates

Coverage

0 articles

INCIDENT TIMELINE

✓ Resolved2026-09-15 11:15 UTC

This incident has been resolved.

monitoring2026-09-15 10:50 UTC

A fix has been deployed for Claude Mythos 5.1 and Claude Fable 5.1 and we are monitoring to ensure it has resolved the issue.

investigating2026-09-15 09:52 UTC

We are investigating elevated errors on requests to Claude Mythos 5.1 and Claude Fable 5.1. We will provide an update as soon as possible.

investigating2026-09-15 09:48 UTC

We are investigating elevated errors on requests to Claude Mythos 5.1 and Claude Fable 5.1. We will provide an update as soon as possible.

Internal ID

461bd59c-26a5-421d-869c-a3173951774a

External ID

6304r9jjhj34

🕐 Started

2026-09-15 09:48 UTC

🔄 Last Updated

2026-09-15 11:15 UTC

✓ Resolved

2026-09-15 11:15 UTC

MAJOR

Impact Level

1h 26m

Total Duration

Status Updates

Affected Components

claude.aiClaude API (api.anthropic.com)Claude CodeClaude Cowork

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