Anthropic

TL;DR Claude Mythos is Anthropic’s most powerful model to date, scoring 93.9% on SWE-bench and 97.6% on USAMO 2026 - a 55-point leap over rival models It is not publicly available; Anthropic restricted access to 12 vetted companies through Project Glasswing, focused on defensive cybersecurity Mythos autonomously identified thousands of zero-day vulnerabilities, including a 27-year-old unpatched OpenBSD bug - making its offensive potential too dangerous to democratize This marks a shift away from open innovation toward controlled deployment, where the most capable AI may never be publicly released The Mythos story forces a rethink of how we evaluate AI: benchmark performance and public availability are no longer the same thing Anthropic built its most capable model to date, demonstrated it autonomously discovering thousands of zero-day vulnerabilities, and then declined to release it. That is the Mythos story, and it is worth sitting with rather than rushing past. The benchmarks are striking, but the decision not to publish is the more consequential part - it signals a real shift in how frontier AI labs are thinking about deployment. ...

TL;DR Claude Mythos Preview set new records across coding, mathematics, and reasoning: 93.9% on SWE-bench Verified, 97.6% on USAMO 2026, and leads GPT-5.4 on every shared benchmark The USAMO result - a 55-point jump over Claude Opus 4.6 - suggests genuinely different reasoning capabilities, not just incremental improvement, and Anthropic screened against memorization concerns Despite dominating benchmarks, Mythos is not publicly available because it autonomously discovered thousands of zero-day vulnerabilities across every major OS and browser Access is restricted to 12 major tech and finance companies via Project Glasswing, a defensive cybersecurity research initiative backed by $100M in Anthropic usage credits The wider implication: we have entered an era where “the best model” and “the publicly available model” may be permanently different things, with security becoming a deployment constraint alongside capability Anthropic released Claude Mythos Preview on April 7, 2026 - and immediately announced it won’t be publicly available. ...

TL;DR An internal debugging file was accidentally included in a public package update, exposing a compressed archive of roughly 500,000 lines of code across around 2,000 files - not a breach, but a packaging mistake The leaked material revealed unreleased features including persistent memory, an always-on autonomous background assistant, and multi-device remote access Competitors gained rare visibility into Anthropic’s development pipeline and longer-term product direction, which is the primary competitive damage The incident undermines Anthropic’s safety-first positioning, particularly because it was the second such exposure in just over a year The broader lesson for the AI industry: internal operational security is becoming as critical as defending against external threats, especially as AI tools target enterprise customers Anthropic’s Claude Code has been making waves as one of the most capable AI coding assistants available, but a significant internal leak has exposed the underlying technology behind the platform for the second time in just over a year. The incident raised fresh concerns about how the company handles sensitive internal information and operational security. ...