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AWS announces Claude Fable 5, the first generally available Mythos-class model

Claude Fable 5 delivers Mythos-level capabilities combined with additional safeguards, and can be accessed through Amazon Bedrock or the Anthropic-operated Claude Platform on AWS. Claude Mythos 5, the same model without those safety classifiers, is available only to a small group of customers.

AWS has announced the general availability of Claude Fable 5, making Mythos-level capabilities available to all customers with strong safeguards for broader use. Fable 5 is state-of-the-art on nearly all tested benchmarks and offers significant advancements in autonomous knowledge work and coding for developers and enterprises building production AI applications. It is designed for professional tasks in finance, legal, marketing, sales, data, and engineering, proactively updating its skills based on learnings, developing evaluation harnesses, and verifying its work before delivery. Customers can access Claude Fable 5 through Amazon Bedrock, which keeps data within AWS infrastructure and provides access through a unified service with AWS-managed features like Guardrails, Knowledge Bases, and regional data residency. Alternatively, the Claude Platform on AWS, operated by Anthropic, offers direct access to Anthropic's native Claude platform experience with unified AWS billing and authentication. Claude Mythos 5, the same model without those safety classifiers, is available to a small group of customers.

Read the original AWS announcement

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