Claude Fable 5
Claude Fable 5 was announced by Anthropic on June 9, 2026 as a generally available Mythos-class model. Anthropic said its safeguards could route some requests to Claude Opus 4.8 instead.
Status
This is a historical release note, not a current model-selection guide. Anthropic's current models overview lists Claude Fable 5.1, rather than Claude Fable 5. Check the current overview and the relevant model page before choosing an API model or relying on token limits, pricing, effort controls, or platform availability.
Sources
linked from