[retroactive] Elevated errors on Claude Haiku 3.5 and Claude Haiku 3

Incident Report for Claude

Resolved

This incident has been resolved.

Posted Sep 20, 2025 - 10:41 UTC

Investigating

From Sep 19 19:00 PT (Sep 20 02:00 UTC) until Sep 19 22:00 PT (Sep 20 05:00 UTC) the Claude Haiku 3 model experienced a very high error rate.

From Sep 19 19:30 PT (Sep 20 02:30 UTC) until Sep 19 20:30 PT (Sep 20 03:30 UTC) the Claude Haiku 3.5 model experienced a very high error rate.

This is a retroactive incident.

Posted Sep 20, 2025 - 10:37 UTC

This incident affected: claude.ai and Claude API (api.anthropic.com).