# Setup

Install `@addresszen/sdk` and create a client with your API key. The SDK runs in browsers and Node.js 22 or later and uses the runtime's native `fetch`.

```bash
npm install @addresszen/sdk
```

client.tsts

```ts
import { createZenClient } from "@addresszen/sdk";

const client = createZenClient({ apiKey: "ak_test" });
```

## Which options does the client take?

| Option      | Type           | Purpose                                                       |
| ----------- | -------------- | ------------------------------------------------------------- |
| `apiKey`    | `string`       | Required API key, sent as `api_key`                           |
| `userToken` | `string`       | Management Key for account operations. Keep it on your server |
| `baseUrl`   | `string`       | Defaults to `https://api.addresszen.com/v1`                   |
| `fetch`     | `typeof fetch` | Custom fetch implementation for tests or request handling     |

## When do I need a Management Key?

Set `userToken` to a Management Key only to call the account operations that need it: key details, usage and logs, licensees and configs. Each [operation page](/docs/sdks/typescript/endpoints/.md) says whether it needs one. A Management Key controls your account, so keep it on your server and never use it in a client that runs in the browser. The SDK sends it in the `Authorization` header, and only to operations that accept it.

## What else do I need to install?

The root package has no runtime dependencies. Install `@tanstack/react-query` or `@tanstack/preact-query` only when using the matching [adapter](/docs/sdks/typescript/react.md#how-do-i-use-tanstack-query).

## Which module formats are supported?

TypeScript consumers can use either NodeNext or bundler module resolution. CommonJS consumers can use `require("@addresszen/sdk")`. Use ESM imports for tree-shaking.