MODELS
by Anthropic
Claude Fable 5 is an Anthropic Claude model described as a Mythos-level model for ambitious long-running work.
Claude Fable 5 is identified in Anthropic-provided source excerpts as a Claude model with API model ID `claude-fable-5`. Anthropic’s product-page excerpt describes it as a Mythos-level model for ambitious long-running work and says the page states pricing, while Anthropic’s announcement excerpt says Claude Fable 5 was announced on June 9, 2026 as a Mythos-class model made safe for general use. Claude API documentation excerpts describe Claude Fable 5 as Anthropic’s most capable widely released model, with a 1M context window and up to 128k output tokens. Availability should be verified before production use because the supplied excerpts conflict: one product-page excerpt says the model is currently unavailable, while API documentation excerpts say general availability began June 9, 2026.
Evaluate Anthropic’s Claude Fable 5 for ambitious long-running work where the supplied Anthropic excerpts indicate a large context window is relevant. Plan Claude API integrations that need the official model identifier `claude-fable-5`. Estimate costs using Anthropic’s published Claude Fable 5 per-token pricing before sending production traffic.
Last updated Jun 17, 2026