Degraded performance for multiple models

Affected

Anthropic → Claude API (api.anthropic.com)

ResolvedAugust 18, 2026 at 7:01 PMUTC
The issue affecting Claude Opus 5 has been resolved. Impact occurred from 16:11 to 18:23 UTC.
MonitoringAugust 18, 2026 at 6:26 PMUTC
A fix has been implemented and we are monitoring the results.
UpdateAugust 18, 2026 at 5:12 PMUTC
We are investigating elevated errors on requests to Claude Opus 5. We will provide an update as soon as possible.
UpdateAugust 18, 2026 at 4:20 PMUTC
We are investigating elevated errors on requests to Claude Mythos 5, Claude Fable 5, Claude Opus 5, Claude Sonnet 5, Claude Haiku 4.5, and other Claude models. We will provide an update as soon as possible.
InvestigatingAugust 18, 2026 at 4:20 PMUTC
We are investigating reports of degraded performance affecting multiple models. We will provide an update as soon as possible.

kkovac - Degraded performance for multiple models – Incident details