Priced At $10 Per Million Input Tokens And $50 Per Million Output Tokens. Less Than Half The Cost Of Claude Mythos Preview With Safety Classifiers That Trigger In Under 5% Of Sessions And Fall Back To Opus 4.8, Fable 5 Is Available On All Subscription Plans At No Extra Cost Through June 22
According to Anthropic, Claude Fable 5 is a Mythos-class model that Anthropic has made safe for general use. Fable 5’s capabilities exceed those of any model Anthropic has ever made generally available and 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.
Stripe reported that Fable 5 compressed months of engineering into days. In a 50-million-line Ruby codebase, the model performed a codebase-wide migration in a day that would otherwise have taken a whole team over two months by hand. On vision tasks, Fable 5 beat Pokémon FireRed with a minimal, vision-only harness, where previous Claude models struggled even with helper tools.
For a small group of cyberdefenders and infrastructure providers, Anthropic is also launching Claude Mythos 5 — the same underlying model as Fable 5, but with the safeguards lifted in some areas. It has the strongest cybersecurity capabilities of any model in the world.
Using Mythos 5, Anthropic’s internal protein design experts accelerated aspects of the drug design process by around ten times. Nine of the 14 protein targets from the study yielded strong candidates for drug design.
Safety classifiers trigger in less than 5% of sessions. When triggered, the response is automatically handled by Claude Opus 4.8 instead. Fable 5 and Mythos 5 are priced at $10 per million input tokens and $50 per million output tokens — less than half the price of Claude Mythos Preview.
To check out our previous coverage on Anthropic, AI models, and the AI industry, read our articles here.
