Anthropic Releases Claude Fable 5 along with Providing Mythos 5 to Select Groups
Anthropic announced it is launching Claude Fable 5, a Mythos-class model made safe for general use.
According to the company, “Fable 5’s capabilities exceed those of any model we’ve ever made generally available. It is state-of-the-art on nearly all tested benchmarks of AI capability, showing exceptional performance in software engineering, knowledge work, vision, scientific research, and many other areas. The longer and more complex the task, the larger Fable 5’s lead over our other models.”
Without safeguards, Fable 5’s capabilities in areas such as cybersecurity could be misused to cause serious damage, the company said. Launching with safeguards mean queries on some topics will instead receive a response from Anthropic’s next-most-capable model, Claude Opus 4.8.
The company is also launching Claude Mythos 5 for a small group of cyberdefenders and infrastructure providers. It’s the same underlying model as Fable 5, but with the safeguards lifted in some areas, the vendor said.
Mythos 5 will initially be deployed through Project Glasswing, in collaboration with the U.S. government, as an upgrade to Claude Mythos Preview. It has the strongest cybersecurity capabilities of any model, Anthropic said.
“The capabilities of models such as Fable 5 and Mythos 5 have the potential to do profound good for the world,” the company stated.
Fable 5 and Mythos 5 are being offered at $10 per million input tokens and $50 per million output tokens—less than half the price of Claude Mythos Preview.
“Claude Fable 5 is a real step forward for the developers GitHub serves. In our early testing, it took on complex, long-horizon coding tasks with a level of autonomy and reliability that exceeds previous benchmarks. But what excites us most is the direction it points: a future where developers can hand increasingly ambitious work to agents and trust the results across the software life cycle,” said Mario Rodriguez, chief product officer at GitHub.
For more information about this news, visit www.anthropic.com.
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