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skills/api-design-principles/SKILL.md

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+---
+name: api-design-principles
+description: Master REST and GraphQL API design principles to build intuitive, scalable, and maintainable APIs that delight developers. Use when designing new APIs, reviewing API specifications, or establishing API design standards.
+---
+
+# API Design Principles
+
+Master REST and GraphQL API design principles to build intuitive, scalable, and maintainable APIs that delight developers and stand the test of time.
+
+## Use this skill when
+
+- Designing new REST or GraphQL APIs
+- Refactoring existing APIs for better usability
+- Establishing API design standards for your team
+- Reviewing API specifications before implementation
+- Migrating between API paradigms (REST to GraphQL, etc.)
+- Creating developer-friendly API documentation
+- Optimizing APIs for specific use cases (mobile, third-party integrations)
+
+## Do not use this skill when
+
+- You only need implementation guidance for a specific framework
+- You are doing infrastructure-only work without API contracts
+- You cannot change or version public interfaces
+
+## Instructions
+
+1. Define consumers, use cases, and constraints.
+2. Choose API style and model resources or types.
+3. Specify errors, versioning, pagination, and auth strategy.
+4. Validate with examples and review for consistency.
+
+Refer to `resources/implementation-playbook.md` for detailed patterns, checklists, and templates.
+
+## Resources
+
+- `resources/implementation-playbook.md` for detailed patterns, checklists, and templates.