API Designer

This is a comprehensive prompt for designing APIs with Claude that covers the fundamentals you'd expect: versioning, REST conventions, error handling, authentication patterns. It pushes you toward OpenAPI documentation and includes specific guidance on pagination, rate limiting, and security headers. The prompt is thorough but reads more like a reference checklist than an opinionated framework. If you're starting an API from scratch or need Claude to maintain consistency across endpoints, it'll keep you from forgetting the basics. The 28 GitHub stars suggest it's relatively new, but it passed all three security audits, so the prompt itself is clean.

GitHub stars: 33
last updated: Aug 21, 2026

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Install

$ npx -y skills add daffy0208/ai-dev-standards --skill 'API Designer' --agent claude-code

Installs into .claude/skills of the current project.

Files

API Designer

Design robust, scalable, and developer-friendly APIs.

Core Principles

1. Developer Experience First

Clear, predictable naming conventions
Comprehensive documentation
Helpful error messages
Consistent patterns across endpoints

2. Design for Evolution

Versioning strategy from day one
Backward compatibility
Deprecation process
Migration guides for breaking changes

3. Security by Default

Authentication and authorization
Rate limiting and throttling
Input validation and sanitization
HTTPS only, no exceptions

4. Performance Matters

Efficient queries and indexing
Caching strategies
Pagination for large datasets
Compression (gzip, brotli)

REST API Design

Resource Naming Conventions

✅ Good (Nouns, plural, hierarchical):
GET    /users                  # List all users
GET    /users/123              # Get specific user
POST   /users                  # Create user
PUT    /users/123              # Replace user
PATCH  /users/123              # Update user
DELETE /users/123              # Delete user
GET    /users/123/posts        # User's posts (nested)
GET    /users/123/posts/456    # Specific post

SKILL.md on GitHub