Claude outage: Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1

Affected components

• Claude API (api.anthropic.com)
• Claude Code
• Claude Cowork
• claude.ai

1. resolvedOct 5, 2026, 13:21 UTC

   The issue affecting Claude Mythos 5.1 and Claude Fable 5.1 has been resolved. Impact occurred from 05:40 PT / 12:40 UTC to 06:10 PT / 13:10 UTC.

2. investigatingOct 5, 2026, 13:05 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.

What APIStatus.watch saw

• Oct 5, 2026, 13:09 UTCoperational → degraded
• Oct 5, 2026, 13:23 UTCdegraded → operational

Other services with incidents at the same time

Overlapping incidents aren't necessarily related.

• Akamai: Origin Server Connectivity Issues with Elevated Errors in APAC RegionMinor · Sep 22, 2026, 14:28 UTC
• Cloudflare: Cloudflare One Clients are incorrectly challenged on some sitesMinor · Sep 22, 2026, 19:23 UTC
• Zoom: Service Degradation Affecting Customer Using Polycom Devices Going OfflineMinor · Sep 25, 2026, 17:45 UTC
• Twilio: MMS Delivery Delays from a Subset of Twilio Long Codes to GCI United StatesMinor · Sep 26, 2026, 03:16 UTC
• Clerk: Development instances only - Apple rejecting emailsMinor · Sep 28, 2026, 15:23 UTC
• Supabase: Intermittent latency in Eastern USMinor · Sep 29, 2026, 16:26 UTC
• Supabase: Intermittent latency in Eastern USMinor · Sep 29, 2026, 16:26 UTC
• Snyk: Issues API V3 Service - DegradedMinor · Oct 3, 2026, 19:49 UTC
• OpenAI: Elevated Work Mode errorsMinor · Oct 5, 2026, 07:03 UTC
• Twilio: SMS Delivery Delays and Failures between Twilio Long Codes and Multiple Networks in FranceMinor · Oct 5, 2026, 09:43 UTC

How often does Claude have incidents?

Claude reported 53 incidents in the last 90 days, 25 of them major or critical. A typical incident lasted 1h 4m. See Claude's uptime and incident history