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    "headline": "Anthropic launches Claude Fable 5.1 and Mythos 5.1 with specialized safeguards",
    "dek": "Anthropic makes Claude Fable 5.1 generally available and releases Mythos 5.1 for trusted partners.",
    "prose": "Anthropic announced the general availability of the Claude Fable 5.1 model. [^1]\n\nAnthropic launched Claude Fable 5.1 and Mythos 5.1, its most capable AI models to date, which share the same base model but differ in safety guardrails. [^2]\n\nAnthropic released Fable 5.1 and Mythos 5.1, two new AI models, as announced on its website. [^3]\n\nAnthropic released a new model named Mythos 5.1 specifically for trusted partners. [^4]\n\nThe Mythos 5.1 model includes specific safeguards designed for cybersecurity applications. [^5]\n\nAnthropic reduced the cost of cache reads from $1 to $0.25 per million tokens to achieve the price reductions, while keeping other API prices unchanged at $10 per million input tokens and $50 per million output tokens. [^6]\n\nAnthropic stated that the new models can cut costs by up to 45 percent, with Fable 5.1 costing about 25 percent less than Fable 5 for typical workloads. [^7]\n\nOn the Terminal-Bench-Science 0.1 benchmark, Fable 5.1 scored 52.6 percent, more than double the 24.7 percent score of Fable 5. [^8]\n\nAnthropic claims Fable 5.1 will cost about 25% less than Fable 5 for typical token-based workloads, with savings up to approximately 45% for highly agentic work. [^9]\n\nAnthropic claims Mythos 5.1 developed full working exploits in 98% of trials, up from 88%. [^10]",
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      "statement": "Anthropic announced the general availability of the Claude Fable 5.1 model.",
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