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

# Introduction

> Welcome to the Simple AI voice platform documentation

## What is Simple AI?

Simple AI is a voice AI platform that lets you build, deploy, and manage AI-powered phone agents. Your agents can make outbound calls, answer inbound calls, send and receive SMS, and be embedded directly in your website — all from a single platform.

## What You Can Build

* **Outbound calling agents** that reach contacts with personalized conversations
* **Inbound support agents** that answer calls on your phone numbers 24/7
* **SMS agents** that hold text conversations alongside voice
* **Web chat agents** embedded in your website via the [web widget](/web-widget)
* **Outbound campaigns** that contact lists of recipients at scale with retry logic and scheduling

## How It Works

1. **Create an agent** — define the personality, prompt, tools, and knowledge your agent needs. Use a simple prompt for quick setups, or build a multi-step flow for complex scenarios. See [Agents](/agents).
2. **Connect a phone number** — buy a number through Simple AI or bring your own via [SIP integration](/sip-integration). See [Phone Numbers](/numbers).
3. **Make calls** — trigger outbound calls through the [API](/api-reference/calls/create-call), the dashboard, or [campaigns](/campaigns). Attach agents to numbers for inbound calls.
4. **Analyze results** — use [analyzers](/analyzers), [tags](/tags), and [sentiment analysis](/call-sentiment) to extract structured insights from every conversation.
5. **Integrate with your systems** — connect [tools](/tools) so agents can look up data, update records, and take actions during calls. Use [webhooks](/webhooks) to push real-time call events to your application.

## Key Concepts

| Concept                          | What It Does                                                                 |
| -------------------------------- | ---------------------------------------------------------------------------- |
| [Agents](/agents)                | Define how your AI behaves — prompt, voice, tools, and conversation flow     |
| [Calls](/calls)                  | Inbound and outbound voice conversations handled by your agents              |
| [Phone Numbers](/numbers)        | Numbers your agents use to make and receive calls                            |
| [Campaigns](/campaigns)          | Batch outbound calling with scheduling, retries, and goal tracking           |
| [Tools](/tools)                  | API connections that let agents interact with external services during calls |
| [Knowledge Base](/knowledgebase) | Reference material your agents can access during conversations               |
| [Analyzers](/analyzers)          | Post-call analysis that extracts structured data from transcripts            |
| [Tags](/tags)                    | Labels for organizing and filtering calls by outcome or topic                |
| [Webhooks](/webhooks)            | Real-time event notifications pushed to your application                     |

## Quick Start

The fastest way to get started is to create a call with an inline agent using the API:

```bash theme={null}
curl -X POST "https://api.usesimple.ai/api/v1/calls" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to_number": "+15551234567",
    "from_number": "+15559876543",
    "prompt": "You are a friendly assistant calling to confirm an appointment."
  }'
```

You can find your API key in the Simple AI dashboard under **Settings > API Keys**.

For more control, create a reusable agent first and then reference it by ID when making calls. See the [API reference](/api-reference/introduction) for the full set of endpoints.

## Getting Help

* **Email**: [support@usesimple.ai](mailto:support@usesimple.ai)
* **Enterprise**: [Contact us](https://form.typeform.com/to/uldus6IZ) for custom plans, SIP integration, and dedicated support