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    "headline": "Anthropic Unveils Fable 5.1 for Autonomous Long-Running AI Work",
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    "prose": "Anthropic has released version 5.1 of its Fable platform. [^1]\n\nPCWorld reported that Anthropic's Claude AI models, specifically the updated Fable and Mythos versions, include a watermarking feature on their replies. [^2]\n\nAnthropic characterizes this specific capability upgrade as a much bigger deal than a standard AI improvement. [^3]\n\nThe primary goal of Fable 5.1 is to make AI agents capable of owning and executing long-running work. [^4]\n\nThe hated Fable data retention policy has been entirely removed in the Fable 5.1 update. [^5]\n\nThe announcement was published on Medium. [^6]\n\nThe Fable 5.1 update includes increased caching as a new feature. [^7]",
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      "statement": "Anthropic has released version 5.1 of its Fable platform.",
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