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
- Define consumers, use cases, and constraints.
- Choose API style and model resources or types.
- Specify errors, versioning, pagination, and auth strategy.
- Validate with examples and review for consistency.
Refer to resources/implementation-playbook.md for detailed patterns, checklists, and templates.
Resources
resources/implementation-playbook.mdfor detailed patterns, checklists, and templates.
Limitations
- Use this skill only when the task clearly matches the scope described above.
- Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
- Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.