CI3 REST API Skill

Target Agent: @code-igniter-3-fullstack
Stack: CodeIgniter 3 · RestServer · firebase/php-jwt · MySQL/PostgreSQL · MVC Monolith

Comprehensive reference for building production-grade REST APIs with CodeIgniter 3, covering project structure, controller patterns, JWT authentication flow, CRUD conventions, validation, security hardening, and error handling.

1. Project Structure

Standard CI3 MVC layout for REST API projects: