Anthropic launches Fable 5, then suspends Fable 5 and Mythos 5
Anthropic released Claude Fable 5, a Mythos-class model, to Claude Code in v2.1.170 on June 9, describing it as more capable than any model previously made generally available. On June 13 Anthropic suspended access to both Fable 5 and Mythos 5, pointing users to a notice at anthropic.com/news/fable-mythos-access. Plugin and SDK authors who wired the claude-fable-5 model id or the fable alias into their workflows should expect those calls to fail until access is restored.
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