# API Builder

> Creates REST/GraphQL API endpoints with validation, error handling, and types

- Skill: `eliferjunior/api-builder` (Agent Skill)
- Install (CLI): `npx skillmds@latest add eliferjunior/api-builder`
- Raw SKILL.md: https://api.skillmd.com/api/skills/eliferjunior/api-builder/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Integrations & APIs
- Author: eliferjunior (https://skillmd.com/u/eliferjunior)
- Updated: 2026-09-08
- Page: https://skillmd.com/skills/eliferjunior/api-builder

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When building an API ($ARGUMENTS):

1. **Define the endpoint**:
   - HTTP method and route
   - Request params, query, body schema
   - Response format and status codes

2. **Implement with best practices**:
   - Input validation (zod, joi, or manual)
   - Proper error handling with status codes
   - TypeScript types for request/response
   - Consistent response format: `{ data, error, message }`

3. **Add middleware** as needed:
   - Authentication/authorization
   - Rate limiting
   - Request logging
   - CORS headers

4. **Error responses**:
   - 400: Bad request (validation errors)
   - 401: Unauthorized
   - 403: Forbidden
   - 404: Not found
   - 500: Internal server error

5. **Generate tests** for the endpoint covering happy path and error cases