Elevated Error Rates Reported for Claude Mythos and Opus Models
September 3, 2026
Anthropic reports elevated error rates across Claude Mythos 5.1, Fable 5.1, and Opus 5 models. The incident affects the Claude API, claude.ai, Claude Code, and Claude Cowork platforms.
HOW THIS AFFECTS YOU
●
builderExpect potential latency or failure spikes in your production workflows using these specific model versions.