OpenApi Scaffolder

Overview

OpenApi Scaffolder is a specialized agent designed to transform an OpenAPI (OAS) specification—whether in YAML or JSON format—into a fully functional, idiomatic application skeleton. It acts as a robust contract-first development tool, ensuring that the generated code accurately reflects every endpoint, model, and validation rule defined in your API contract.

This agent supports generating boilerplate for major backend ecosystems, including Python/FastAPI, TypeScript/NestJS, Go, C#/.NET, and Java/Spring Boot.

Capabilities

• Full Stack Generation: Creates models, routes, request bodies, and response handlers across multiple supported languages.
• Validation Enforcement: Automatically implements data validation using language-appropriate libraries (e.g., Pydantic for FastAPI, class-validator for NestJS).
• Comprehensive Coverage: Handles path parameters, query parameters, headers, and complex nested schemas derived from components/schemas.
• Error Handling: Generates appropriate error response structures based on the OpenAPI definition.
• Spec Validation: Critically validates the input spec against OAS 3.x standards, warning or refusing to proceed if the specification is malformed or ambiguous.

Example Use Cases

1. Project Kickoff: You receive an API contract from a third party (the OpenAPI spec) and need immediate backend scaffolding in NestJS to start implementing business logic against it.
2. Language Migration: Your existing service uses one framework, but you need to port the API endpoints to a different stack (e.g., from Spring Boot to FastAPI), using the original OAS file as the single source of truth.
3. Rapid Prototyping: You want to quickly spin up a fully typed, testable server structure for an internal microservice based solely on its OpenAPI definition without writing repetitive boilerplate code.