to-openapiOpenAPI from any schema

Generate OpenAPI 3.1 specs from Zod, ArkType, Valibot, and any Standard Schema library.

Schema Agnostic

Works with any library implementing the Standard Schema interface — Zod, ArkType, Valibot, and more. No lock-in.

Use the declarative openapi() function for simple specs, or the chainable OpenAPI class builder for dynamic construction.

Transform routes, schemas, and entire documents with composable plugins. Ships with bearer auth, auto tags, and error responses.

Combine multiple OpenAPI documents with merge() — perfect for microservices and modular architectures.

Schemas are automatically deduplicated and promoted to components/schemas with $ref references.

Full TypeScript support with exported types for routes, plugins, schemas, and every OpenAPI construct.