> ## Documentation Index
> Fetch the complete documentation index at: https://docs.belvedir.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Install the Fractal Loop SDK for Your Node.js Project

> Add @fractalresearch/loop to your Node.js project and start capturing LLM traces automatically — no manual instrumentation needed.

The Belvedir Node SDK auto-instruments the major LLM providers with a single `initialize()` call.

## Install

```bash theme={null}
npm install @fractalresearch/loop
```

## Initialize

The SDK patches your LLM client the moment `initialize()` runs, so it must run **before the LLM SDK is imported**. In Next.js use `instrumentation.ts` at the project root — see the [Next.js guide](/guides/nextjs). In a plain Node process, call it at the top of your entry file:

```ts theme={null}
import { initialize } from "@fractalresearch/loop";

initialize({
  apiKey: process.env.FRACTAL_API_KEY,
  appName: "my-agent",
});

// import OpenAI/Anthropic *after* initialize()
```

For bundled or ESM environments, pass your LLM SDKs to `instrumentModules` so they're patched directly — see [Configuration](/sdk/configuration).

## Next steps

* [Configuration](/sdk/configuration) — every option accepted by `initialize()`.
* [Providers](/sdk/supported-providers) — every LLM provider we auto-instrument.
* [Python SDK](/sdk/python) — same concepts, snake\_case, context managers.