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skills/auth-implementation-patterns/SKILL.md

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+---
+name: auth-implementation-patterns
+description: Master authentication and authorization patterns including JWT, OAuth2, session management, and RBAC to build secure, scalable access control systems. Use when implementing auth systems, securing APIs, or debugging security issues.
+---
+
+# Authentication & Authorization Implementation Patterns
+
+Build secure, scalable authentication and authorization systems using industry-standard patterns and modern best practices.
+
+## Use this skill when
+
+- Implementing user authentication systems
+- Securing REST or GraphQL APIs
+- Adding OAuth2/social login or SSO
+- Designing session management or RBAC
+- Debugging authentication or authorization issues
+
+## Do not use this skill when
+
+- You only need UI copy or login page styling
+- The task is infrastructure-only without identity concerns
+- You cannot change auth policies or credential storage
+
+## Instructions
+
+- Define users, tenants, flows, and threat model constraints.
+- Choose auth strategy (session, JWT, OIDC) and token lifecycle.
+- Design authorization model and policy enforcement points.
+- Plan secrets storage, rotation, logging, and audit requirements.
+- If detailed examples are required, open `resources/implementation-playbook.md`.
+
+## Safety
+
+- Never log secrets, tokens, or credentials.
+- Enforce least privilege and secure storage for keys.
+
+## Resources
+
+- `resources/implementation-playbook.md` for detailed patterns and examples.