Outgoing Phone Calls

This guide will help you set up and make your first automated call using Ultravox and Twilio.

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Prerequisites

• Node.js 20 or higher
• A Twilio account with:
  • Account SID
  • Auth Token
  • Phone Number
• An Ultravox API key

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Set-up and Installation

pnpm install

npm install

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Making Your First Call

The AI assistant will introduce itself as Steve and have a conversation with the recipient. To make a call you need to update the variables for keys and phone numbers. You may also update the system prompt.

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Update Configuration

• TWILIO_ACCOUNT_SID: Your Twilio Account SID from the Twilio Console
• TWILIO_AUTH_TOKEN: Your Twilio Auth Token
• TWILIO_PHONE_NUMBER: The Twilio phone number to make calls from
• DESTINATION_PHONE_NUMBER: The recipient’s phone number
• ULTRAVOX_API_KEY: Your Ultravox API key
• SYSTEM_PROMPT: Instructions for the AI agent’s behavior

import twilio from 'twilio';
import https from 'https';

// Twilio configuration
const TWILIO_ACCOUNT_SID = 'your_twilio_account_sid_here';
const TWILIO_AUTH_TOKEN = 'your_twilio_auth_token_here';
const TWILIO_PHONE_NUMBER = 'your_twilio_phone_number_here';
const DESTINATION_PHONE_NUMBER = 'the_destination_phone_number_here';

// Ultravox configuration
const ULTRAVOX_API_KEY = 'your_ultravox_api_key_here';
const SYSTEM_PROMPT = 'Your name is Steve and you are calling a person on the phone. Ask them their name and see how they are doing.';

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Start the Call

Once you’ve configured and saved everything, start the call:

pnpm start

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Next Steps

Ultravox Realtime provides telephony integrations for Telnyx, Twilio, and Plivo. Learn more here.