Modern authentication implementation for 2026 - passkeys (WebAuthn), OAuth (Google, Apple), magic links, and cross-device sync. Use for passwordless-first authentication, social login setup, Supabase Auth, Next.js auth flows, and multi-factor authentication. Activate on "passkeys", "WebAuthn", "Google Sign-In", "Apple Sign-In", "magic link", "passwordless", "authentication", "login", "OAuth", "social login". NOT for session management without auth (use standard JWT docs), authorization/RBAC (use security-auditor), or API key management (use api-architect).
This skill does not declare a tool allowlist. The agent host applies whatever default tools are available at runtime.
SKILL.md / Manifest
https://raw.githubusercontent.com/erichowens/some_claude_skills/main/.claude/skills/modern-auth-2026/SKILL.mdRegistry
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