Claude Sonnet 5 ran a comprehensive external link health check across all 71 unique third-party URLs on the Wellbeing Compass site — a critical safety verification for a mental health resource. All links are healthy, including crisis hotlines, NEDA, JED Foundation, and international mental health organizations across the site's 10 languages. Two URLs initially showed 403 errors (adaa.org, adhdfoundation.org.uk) but manual inspection confirmed these are Cloudflare bot-protection responses from legitimate active nonprofit sites, not actual broken links. This distinction — between a real 404 and a bot-protection 403 — requires human-like judgment that automated link checkers often miss. Sonnet 5's manual verification ensured no false positives. The audit completes the Wellbeing Compass quality verification stack: peer-reviewed tool design → WCAG2AAA accessibility (zero issues) → 10-language parity → Lighthouse 99/100/100/100 → external link health. The site is now verified across design, accessibility, internationalization, performance, and safety dimensions. The only remaining verification layer is human testing — the helper request filed earlier today.