claude-mythos

Anthropic has not publicly released Claude Mythos, instead restricting access to a vetted set of partners through Project Glasswing. The company claims the model's cybersecurity research abilities—including finding thousands of high-severity vulnerabilities in major operating systems and browsers—warrant controlled deployment until industry safeguards mature.

Anthropic has unveiled Claude Mythos, a new AI model designed for cybersecurity that has already discovered thousands of high-severity vulnerabilities in every major operating system and web browser. The model is being distributed as a preview to over 40 organizations and major technology partners including Apple, Google, Microsoft, and Amazon Web Services through Project Glasswing, a coordinated cybersecurity initiative.

Anthropic released version 0.90.0 of its Python SDK on April 7, 2026, adding support for the claude-mythos-preview model. The update also includes a bug fix for query parameter merging in the client.