How to Build Your First Voice AI Agent on the Syllable Platform

Josh York, Chris Bergt

Published: Mar 31, 2025

Welcome to the Syllable Platform, where creating and deploying powerful AI agents is easier than ever. In this tutorial, we'll walk you through how to build your first voice AI agent from scratch. Whether you're building a customer service assistant, a virtual loan advisor, or something totally custom, this guide will help you get started fast.

Step 1: Create a Prompt

Before your agent can do anything useful, it needs to know how to behave, and that starts with creating a prompt.

• Head to the Prompts section and click "New Prompt"
• Fill in the required fields: Name, Description, etc.
• Choose your model provider (OpenAI, Azure, or Google)
• In the large prompt field, write custom instructions or paste in a ready-to-use template
• You can also add tools to the prompt to enable actions like calling APIs or transferring calls
• Click Save

Step 2: Add a Message

Define the first message your agent will say when someone calls.

• Go to the Messages section and click "New Message"
• Fill out the default message (this is your agent's greeting)
• You can optionally add rules to customize the message for holidays or special cases
• Click Save

Step 3: Create Your Agent

• Head to the Agents section and click "New Agent"
• Give your agent a name and optional description
• Select the prompt and message you just created
• Set the time zone, choose Google Speech-to-Text, and optionally add languages and sound effects
• Click Save

Your agent is now live in the system, and you can test it in the preview window immediately.

Step 4: Set Up a Voice Channel

• Go to the Channels section and click "New Channel"
• Under Mode, select Voice
• Name your channel and assign a target phone number
• Add a fallback number in case something goes wrong
• Connect this channel to your newly created agent

Now just call the number, and your agent will pick up the phone!

Start Building Today

With Syllable, you can create voice, chat, and multimodal agents without complex setup or code. This is just the beginning. Stay tuned for more tutorials, and start building AI agents for every idea.

Need Inspiration?

Explore agents in our showcase including Real Estate, eCommerce, Healthcare, Financial Services, and IT Support agents.