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

# Introduction

# Voice AI Agent Function calls

**Function Calls** (also known as Tool Calls) are the mechanism through which your AI agent interacts with the outside world. They allow the agent to perform actions based on the conversation flow.

## How it Works

Movoice AI uses the "Tool Use" capabilities of modern LLMs (like GPT-4 and Claude).

1. **Detection**: The agent listens to the user.
2. **Logic**: The LLM determines if a specific tool is needed to fulfill the user's request.
3. **Execution**: Movoice AI executes the function (e.g., transfers a call or pings your API).
4. **Response**: The agent continues the conversation based on the result of the function.

## Core Functions

### [Transfer Calls](transfer-calls.md)

Connect the user directly to a human or another automated system.

### [Calendar Integration](book-calendar.md)

Check availability and book meetings on Calendly or Cal.com.

### [Custom Function Calls](custom-functions.md)

Build your own specialized tools that connect to your proprietary database or CRM.

## Getting Started

To enable function calls, navigate to the **Tools** tab in the Agent Studio. You must also define in your system prompt **exactly** when the agent should use these tools.