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

# Overview

> The essential guides for making your first API call, rendering UI, and connecting to data.

This section covers the fundamental building blocks of C1. These guides walk you through the complete, end-to-end flow: from making your first backend API call to rendering a dynamic, data-driven UI on the frontend.

Mastering these concepts is the first step to building any application with C1.

## Guides in This Section

* [**Integrating C1 in your backend**](/guides/implementing-api)
  Call the C1 API from your backend using the OpenAI-compatible endpoint.

* [**Rendering C1 Responses into live UI**](/guides/rendering-ui)
  Use the C1 React SDK to render the API response as interactive UI components.

* [**Streaming**](/guides/streaming)
  Stream responses from the API to create a real-time, responsive user experience.

* [**Guiding UI generations**](/guides/guiding-outputs)
  Use system prompts to control the structure and content of the generated UI.

* [**Integrate data via Tool Calling**](/guides/integrate-data/tool-calling)
  Connect C1 to your own data sources and APIs using tool calling.