Anthropic releases Fable 5, bringing capabilities of restricted Mythos model to public with $10/$50 per 1M token pricing

Anthropic has released Fable 5, a new model family that brings many capabilities of its restricted Mythos system to the public. The company will charge $10 per million input tokens and $50 per million output tokens after a free trial period ending June 22.

Performance claims and benchmark positioning

According to Anthropic's internal testing, Fable 5 outperforms the company's previous flagship Opus 4.8, as well as OpenAI's GPT-5.5 and Google's Gemini 3.1 Pro. Anthropic states the model shows its largest advantages on longer, more complex tasks.

The company claims Fable 5 excels at software engineering, drug design, and document analysis, while also improving in areas where previous Claude models underperformed, particularly vision tasks.

Vision capabilities demonstration

Anthropic demonstrated Fable 5's vision improvements through gaming benchmarks. The company's previous model, Claude 3.7 Sonnet, required an overlay interface to play Pokémon Red and had to reevaluate positions between frames, essentially operating blind between actions.

Fable 5 can complete Pokémon FireRed (2004 Game Boy Advance) using only vision input, according to Anthropic. The company says this translates to practical capabilities like extracting precise numbers from scientific figures and rebuilding web application source code from screenshots.

Safety measures and routing

Fable 5 includes automatic routing to the less-capable Opus 4.8 for certain topics as a safety measure. Anthropic acknowledges these safeguards are "tuned conservatively" and will sometimes flag harmless requests, triggering in less than 5 percent of sessions on average.

Mythos 5 and Project Glasswing

Anthropic also released Mythos 5, which runs on the same underlying model as Fable 5 but with fewer safeguards. Mythos 5 will initially be available only through Project Glasswing before expanding to a trusted access program.

Mythos, first revealed in early April through Project Glasswing, was shared with select partners including Apple and NVIDIA to help organizations defend against AI-powered cyberattacks. The project prompted discussions about AI regulation at the White House.

Pricing and availability

Claude subscribers can use Fable 5 without spending usage credits until June 22. After that date, pricing is set at $10 per million input tokens and $50 per million output tokens. Anthropic states it aims to restore Fable 5 as a standard part of subscription plans "when sufficient capacity allows."

What this means

The $50 per million output tokens positions Fable 5 as one of the most expensive publicly available models, signaling Anthropic's confidence in its capabilities for high-value tasks. The conservative safety routing and restricted Mythos 5 access suggest the underlying model has capabilities Anthropic considers risky to deploy widely, continuing a pattern of staged releases for frontier models. The vision improvements, if verified independently, represent meaningful progress in multimodal capabilities beyond text-only tasks.