Anthropic's Claude Fable 5.1 offers improved coding at lower costs
What's the story
Anthropic has launched a major upgrade for Claude, with the introduction of Fable 5.1. The new model promises better performance and lower operating costs than its predecessor, Fable 5. According to Anthropic, "Claude Fable 5.1 sets a new standard in coding, knowledge work, and long-running problem-solving tasks." The company also claims that the upgraded model performs at par or even better than Fable 5 while being more cost-effective in low/medium effort settings.
Cost efficiency
Fable 5.1 will cost around 25% less than its predecessor
Anthropic estimates that Fable 5.1 will cost around 25% less than its predecessor for typical workloads.
This is mainly due to a price cut on cache reads, where the model reuses previously processed and stored inputs.
For more complex tasks, the cost savings could be even higher, going up to as much as 45%.
Claude Fable 5.1 is now available through Claude API, Amazon Web Services, Google Cloud, and Microsoft Azure.
Safety measures
New Enterprise Frontier Safeguards (EFS)
Anthropic has also introduced a new system called Enterprise Frontier Safeguards (EFS) to enhance customer privacy while preventing adversarial use.
The EFS stores data in cloud infrastructure controlled entirely by the customer, not Anthropic.
It will be rolled out to enterprise customers in phases starting later this year. Until then, eligible customers can use Fable 5.1 with zero data retention.
Performance boost
Improved capabilities and safety measures
Fable 5.1 is designed to avoid shortcuts that could compromise quality and can pinpoint and resolve the root causes of software problems.
It also offers improved scientific research capabilities across a range of fields, according to Anthropic's research.
The company also tested both models against chemical/biological risks, cybersecurity threats, agentic safety, alignment using automated evaluations, expert red-teaming exercises with PhD-level biologists & AI experts, among other things.
Enhanced safeguards
Claude Mythos 5.1 variant for cybersecurity, life sciences professionals
Along with Fable 5.1, Anthropic also unveiled Claude Mythos 5.1, a variant tailored for vetted cybersecurity and life sciences professionals under expanded safety controls.
The company says it is identical to Fable but has more permissive safeguards for trusted individuals/organizations whose work may be impacted by the cybersecurity/life sciences restrictions mentioned above.
It will be available through two trusted access programs: Cyber Verification Program (CVP) and Life Sciences Verification Program.