# Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1

- Provider: [Anthropic](https://down.guide/providers/anthropic)
- Confidence: Confirmed
- Impact: Partial outage
- lasted 16m
- started 2026-10-05 13:05 UTC
- claude.ai, Claude API (api.anthropic.com), Claude Code +1
- Anthropic states the impact was 2026-10-04 19:40 UTC to 2026-10-05 13:10 UTC (17h 30m)
- id: DWN-ab85b69e18
- Official page: https://stspg.io/wdqhxt8xt574

## Updates from Anthropic
### 2026-10-05 13:05 UTC: investigating
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.

### 2026-10-05 13:21 UTC: resolved
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.

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