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

# Introduction

> Welcome to the Pika API Reference

## Authentication

Please reach out to the Pika team to get an API url, key, and user id.

The docs provide an outline of what's possible using the Pika API.

All API endpoints are authenticated using an `X-API-KEY` header:

```
curl -H "X-API-KEY: <API_KEY>"
```

## Video Output Retention

Generated videos are only guaranteed to be stored for **30 days**. After this period, they may be automatically deleted. Developers should download and back up any important outputs within this timeframe.

## Prompting Guide

To get the best results with Pika, follow the prompting guides for our different models:

* \[Pika 2.1]: Prompt guide in the works!
* [Pika 2.0](https://mellis-labs.notion.site/Pika-2-0-User-Guide-15f23e1d26f4804187e1e9127036bf8a?pvs=4)
* [Pika 1.5](https://mellis-labs.notion.site/Pika-1-5-User-Guide-11823e1d26f4803c87f4d168064ca224)
* [Pika 1.0](https://mellis-labs.notion.site/PIKA-1-0-GUIDE-db38c821673a44d2984d481519510391)

To use each model, just set the `modelVersion` parameter in the request.