API Design Principles

Master REST and GraphQL API design principles to build intuitive, scalable, and maintainable APIs.

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
• •Creating developer-friendly API documentation

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.

REST Best Practices

• •Use nouns for resources (e.g., /users, /orders)
• •Use HTTP methods correctly (GET, POST, PUT, DELETE, PATCH)
• •Return appropriate status codes
• •Implement proper pagination
• •Version your APIs

GraphQL Best Practices

• •Design schema-first
• •Use meaningful type names
• •Implement proper error handling
• •Consider query complexity limits
• •Use DataLoader for N+1 problems