---
title: "Claude Fable 5 and Claude Mythos 5 \ Anthropic"
source: "https://www.anthropic.com/news/claude-fable-5-mythos-5?utm_term=prospects&utm_campaign=2026-06-09-Email-FounderBuildDay-Prospects&utm_medium=email&_hsenc=p2ANqtz-8bVTMwaN63UECk19stNwEaLRgbWYcVRyDeE_svaRVyawvgzhq7czsO6y9EAwFi_1-Joz0zJto4XQV-3GAUJ3KljQw17g&_hsmi=423056143&utm_content=inline_link&utm_source=hs"
domain: "www.anthropic.com"
type: "article"
summarized_at: "2026-06-09"
canonical: "https://tl-dr.cc/s/claude-fable-5-and-claude-mythos-5-anthropic-i0bV"
---

# Claude Fable 5 and Claude Mythos 5 \ Anthropic

**Source:** [www.anthropic.com](https://www.anthropic.com/news/claude-fable-5-mythos-5?utm_term=prospects&utm_campaign=2026-06-09-Email-FounderBuildDay-Prospects&utm_medium=email&_hsenc=p2ANqtz-8bVTMwaN63UECk19stNwEaLRgbWYcVRyDeE_svaRVyawvgzhq7czsO6y9EAwFi_1-Joz0zJto4XQV-3GAUJ3KljQw17g&_hsmi=423056143&utm_content=inline_link&utm_source=hs)  
**Summarized:** 2026-06-09  

- Anthropic launched Claude Fable 5, a state-of-the-art general-use model with Mythos-class capabilities that exceed all previously available Claude models, showing exceptional performance in software engineering, knowledge work, vision, and scientific research.
- Fable 5 includes safety classifiers that automatically route queries about cybersecurity, biology/chemistry, and model distillation to Claude Opus 4.8, triggering fallback in less than 5% of sessions, balancing capability release with risk mitigation.
- Claude Mythos 5, the same underlying model with safeguards lifted, is deployed through Project Glasswing for cybersecurity professionals and will expand to biology researchers through a trusted access program, with demonstrated impact on infrastructure security and drug design acceleration.
- Fable 5 demonstrates breakthrough autonomous capabilities—completing months of engineering work in days, conducting novel biological research independently, and solving complex long-horizon tasks with minimal human direction—while maintaining alignment levels comparable to earlier Claude models.
- Both models are priced at $10 per million input tokens and $50 per million output tokens, with Fable 5 rolled out conservatively across subscription tiers through June 22 due to expected high demand.

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*AI summary by [tl;dr](https://tl-dr.cc) · [View full page](https://tl-dr.cc/s/claude-fable-5-and-claude-mythos-5-anthropic-i0bV)*