API Reference

Complete API reference for itty-spec. All functions, types, and utilities are documented here.

Core Functions

createContract

Creates a contract object that defines your API operations.

import { createContract } from "itty-spec";

const contract = createContract({
  operationName: {
    path: "/path",
    method: "GET",
    responses: { /* ... */ },
  },
});

createRouter

Creates a router with handlers bound to a contract.

import { createRouter } from "itty-spec";

const router = createRouter({
  contract,
  handlers: {
    operationName: async (request) => {
      // Handler implementation
    },
  },
});

createOpenApiSpecification

Generates an OpenAPI 3.1 specification from a contract.

import { createOpenApiSpecification } from "itty-spec/openapi";

const spec = await createOpenApiSpecification(contract, {
  title: "API Title",
  version: "1.0.0",
  description: "API Description",
  servers: [{ url: "https://api.example.com" }],
});

Type Reference

Types

Complete reference for all TypeScript types used in itty-spec:

• Contract types
• Request types
• Response types
• Helper types

Middleware API

Reference for built-in middleware and custom middleware patterns.

Quick Links

• Contracts Guide - Learn about contract definitions
• Router Configuration - Configure your router
• Type Safety - Understand type inference
• Examples - Working examples

For detailed type definitions, see the TypeScript source code.