Frontier Line and access · releases
Anthropic released Claude Fable 5.1 broadly and Claude Mythos 5.1 to vetted organizations.
Anthropic reportedly released Claude Fable 5.1 and Mythos 5.1, including a 75% reduction in cache-read costs for Fable.
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Anthropic launches Fable 5.1 as AI security worries mountmashable.com, Sep 1What's new in Claude Fable 5.1 - Claude Platform Docsanthropic.com, Sep 1Why Claude switched models in your conversation with Fable 5 or Fable 5.1 | Anthropic Help Centeranthropic.com, Sep 1Claude Fable 5.1 system prompts - Claude Platform Docsplatform.claude.com, Sep 1Migrating to Claude Fable 5.1 and Claude Mythos 5.1 - Claude Platform Docsplatform.claude.com, Sep 1Claude Fable 5.1 Is Out: What Changed, What Broke, and What the Rumor Mill Got Wrongroo.beehiiv.com, Sep 1Anthropic Ships Claude Fable 5.1, More Than Doubling Its Predecessor on Key Benchmarktech.yahoo.com, Sep 1Anthropic's Fable 5.1 is a bit cheaper, a bit smarter, and refuses a lot less - The New Stackthenewstack.io, Sep 1
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