# Source: https://www.quo.com/docs/mdx/api-reference/introduction.md

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

# Introduction

> Welcome to the Quo API!

## Overview

The Quo API enables developers to integrate powerful communication features directly into their applications and workflows. Built on REST principles, our API provides a reliable and secure way to programmatically manage phone communications.

## Key features

<CardGroup cols={2}>
  <Card title="REST architecture" icon="code">
    Industry-standard REST API design with JSON responses for easy integration
  </Card>

  <Card title="Secure authentication" icon="lock">
    API key-based authentication to ensure secure access to your account
  </Card>

  <Card title="JSON responses" icon="brackets-curly">
    All API responses are returned in standardized JSON format
  </Card>

  <Card title="Developer tools" icon="screwdriver-wrench">
    Comprehensive documentation and [resources](/mdx/guides) to accelerate development
  </Card>
</CardGroup>

## Next steps

Ready to dive deeper? Here are some helpful resources:

* [Authentication guide](/mdx/api-reference/authentication) - Learn about securing your API requests

* [Send your first message](/mdx/api-reference/send-your-first-message) - Quick start guide for messaging

* [Build with AI LLMs](/mdx/guides/building-with-ai-llms) - Learn how to utilize this API alongside AI