This is the Anthropic announcement link.
Claude Fable 5 and Claude Mythos 5
https://www.anthropic.com/news/claude-fable-5-mythos-5
Below is content translated and excerpted in part.
Today we are launching Claude Fable 5, a Mythos-tier model designed to be safely used for general purposes.
Fable 5's performance surpasses any model we have publicly released to date. This model achieves state-of-the-art performance on nearly all AI performance test benchmarks and demonstrates outstanding performance in software engineering, knowledge work, vision, scientific research, and many other domains. The longer and more complex the task, the greater the gap Fable 5 demonstrates compared to our other models. ……
We are also launching Claude Mythos 5 for a small number of cyber defense experts and infrastructure providers. This model uses the same base model as Fable 5 but has safety guardrails disabled in some areas. Mythos 5 will be initially deployed through 'Project Glasswing' as an upgraded version of Claude Mythos Preview in collaboration with the U.S. government. This model possesses more powerful cybersecurity capabilities than any other model in the world. We plan to expand access to Mythos 5 through a broader trust-based access program in the near future. ……
Demand for Fable 5 is expected to be very high and is difficult to predict. Fable 5 is fully available starting today on Claude API and pay-as-you-go based Enterprise plans. For subscription plans, we want to provide access as quickly as possible, but plan to roll out more cautiously in phases.
From today through June 22, Fable 5 will be included at no additional cost in Pro, Max, Team, and per-seat based Enterprise plans.
From June 23, Fable 5 will be excluded from those plans. To use it after that, usage credits will be required. We plan to extend the inclusion period if capacity allows.
After that, we plan to offer Fable 5 again as a standard feature in subscription plans as soon as sufficient capacity is secured. We plan to proceed as quickly as possible.
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Excerpt from Anthropic's Twitter(X) post
https://x.com/claudeai/status/2064394151441863006
