The video showcases Mythos, released as Fable 5, a cutting-edge AI model excelling in cybersecurity, bug detection, fixing, UI redesign, and security auditing, outperforming competitors like GPT 5.5 and Claude Opus 4.8 in various benchmarks. Through practical testing on the presenter’s SaaS product, Fable 5 demonstrated superior capabilities in identifying critical vulnerabilities and enhancing user interfaces, positioning it as a valuable tool for developers and cybersecurity professionals.
The video introduces Mythos, released as Fable 5, a new AI model designed primarily for cybersecurity, bug detection, and code fixing. The presenter outlines the testing approach, which includes four different tests focusing on bug detection, bug fixing, UI redesign, and security auditing. Mythos is touted as a revolutionary model capable of identifying security vulnerabilities in major software, developed in collaboration with leading cybersecurity teams to ensure safety and reliability before public release. Benchmark comparisons show Fable 5 outperforming other models like GPT 5.5, Gemini 3.1, and Claude Opus 4.8 across various metrics, including agentic coding, spatial reasoning, and cybersecurity, with particularly impressive results in exploit detection.
The presenter highlights the practical applications of Fable 5, encouraging viewers interested in building real AI applications and automations to join their Build community, which offers tutorials, resources, and personal guidance. The benchmarks reveal Fable 5’s superior performance in coding tasks and cybersecurity, with an 88% score in agentic terminal coding and 78% on the exploit benchmark, significantly higher than competitors. This suggests that Fable 5 could be a valuable tool for cybersecurity professionals and developers looking to identify and fix bugs efficiently.
In the hands-on testing phase, the presenter uses their own SaaS product, Scripty, to evaluate Fable 5’s bug detection and fixing capabilities. Fable 5 identified 23 verified bugs, including critical and high-confidence issues, many related to billing errors such as double charging and promo code misuse. While some bugs were fixed automatically, others required manual intervention. The UI redesign test showed improvements in the pricing page, with a cleaner, more appealing design and corrected pricing details, demonstrating Fable 5’s ability to enhance user interfaces effectively.
The security audit revealed one critical vulnerability and several high and medium-level issues, including promo code misuse, privilege escalation, credit deduction bypass, and unauthenticated debug routes exposing sensitive information. These findings were significant because previous AI models like Claude Opus 4.7 and 4.8, Codex, and GPT 5.5 had not detected these problems. The presenter notes that while some issues stem from legacy code or configuration oversights, Fable 5’s ability to uncover them highlights its advanced security auditing capabilities.
Overall, the presenter expresses strong approval of Fable 5, emphasizing its impressive bug detection, fixing, UI enhancement, and security auditing performance. They plan to continue testing it against other AI models and real-world websites to further explore its capabilities. The video concludes with an invitation for viewers to engage in future tests and discussions, underscoring Fable 5’s potential as a powerful tool for developers and cybersecurity experts alike.