Generate a fully typed TypeScript API client from your OpenAPI spec using telaio gen-client.

Generate API Client

pnpx telaio gen-client

telaio gen-client generates a TypeScript API client from your app's OpenAPI spec. It spins up the app in ephemeral mode (no lifecycle hooks, no open ports), extracts the OpenAPI JSON, and passes it to @hey-api/openapi-ts for code generation.

Peer dependency

pnpm add -D @hey-api/openapi-ts

Configuration

Configure the client in telaio.config.ts:

import { defineConfig } from 'telaio';

export default defineConfig({
  app: 'src/app.ts',  // required: path to your app builder module

  client: {
    output: 'client',   // output directory, relative to project root
    enabled: true,      // set to false to disable generation
    plugins: [
      '@hey-api/sdk',
      '@hey-api/typescript',
      { name: '@hey-api/client-fetch', throwOnError: true },
    ],
  },
});

ClientConfig options

Option	Type	Default	Description
`output`	`string`	`'client'`	Output directory for generated files
`enabled`	`boolean`	`true`	Set to `false` to skip generation (useful in CI)
`plugins`	`array`	Default set	`@hey-api/openapi-ts` plugin list

Default plugins

When plugins is not specified, the following are used:

@hey-api/typescript -- TypeScript type definitions
@hey-api/sdk -- typed SDK functions
@tanstack/react-query -- React Query integration (if installed)

Ephemeral mode

gen-client imports your app module and calls .asEphemeral() before .build(). This skips all onReady and onClose lifecycle hooks, meaning the server never binds to a port and background processes never start. The app is assembled purely to extract the OpenAPI spec.

Your app module should export the builder result, not a started server:

// src/app.ts — export the built app, not app.start()
import { loadConfig, createApp } from 'telaio';

const config = loadConfig({ modules: { server: true, database: true } });

export const app = await createApp({ config })
  .withDatabase()
  .withSwagger({ info: { title: 'My API', version: '1.0.0' } })
  .withApiDocs()
  .withPlugins({ autoload: { dir: 'src/routes' } })
  .build();

Output

The generated client is written to the configured output directory. If Biome is installed in the project, the output is automatically formatted after generation.

client/
  index.ts
  types.gen.ts
  sdk.gen.ts
  @tanstack/
    react-query.gen.ts

Using the generated client

import { client, getUsers, getUserById } from '../client/index.js';

// Configure the base URL once
client.setConfig({ baseUrl: 'https://api.example.com' });

// Use typed functions
const users = await getUsers({ query: { limit: 20, skip: 0 } });
const user = await getUserById({ path: { id: '123' } });

Run telaio gen-client as part of your CI pipeline to keep the client in sync with the API spec. Commit the generated output so consumers of the client do not need to run generation themselves.

Generate API Client

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