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

# Overview

> Base URL, authentication and API conventions.

Base URL:

```
https://api.apinn.io
```

* **Auth**: `X-API-Key` header on every request ([details](/en/authentication)).
* **Format**: all responses are JSON arrays of objects. ISO 8601 timestamps (UTC).
* **Quota**: 5,000 requests/hour, `X-Quota-*` headers ([details](/en/rate-limits)).

The following pages document each endpoint with an interactive **playground** — fill in your key and test live.