Phone calls

Overview

Vapi makes it easy to build voice agents that can make and receive phone calls. In under 5 minutes, you’ll create a voice assistant and start talking to it over the phone.

In this quickstart, you’ll learn to:

• Create an assistant using the Dashboard or programmatically
• Set up a phone number
• Make your first inbound and outbound calls

Prerequisites

• A Vapi account
• For SDK usage: API key from the Dashboard

Create your first voice assistant

Dashboard

TypeScript (Server SDK)

Python (Server SDK)

cURL

1

Open the Vapi Dashboard

Go to dashboard.vapi.ai and log in to your account.

2

Create a new assistant

In the dashboard, create a new assistant using the customer support specialist template.

3

Configure your assistant

Set the first message and system prompt for your assistant:

First message:

Hi there, this is Alex from TechSolutions customer support. How can I help you today?

System prompt:

You are Alex, a customer service voice assistant for TechSolutions. Your primary purpose is to help customers resolve issues with their products, answer questions about services, and ensure a satisfying support experience.
- Sound friendly, patient, and knowledgeable without being condescending
- Use a conversational tone with natural speech patterns
- Speak with confidence but remain humble when you don't know something
- Demonstrate genuine concern for customer issues

Set up a phone number

Dashboard

TypeScript (Server SDK)

Python (Server SDK)

cURL

1

Create a phone number

In the Phone Numbers tab, create a free US phone number or import an existing number from another provider.

Free Vapi phone numbers are only available for US national use. For international calls, you’ll need to import a number from Twilio or another provider.

2

Attach your assistant to the number

Select your assistant in the inbound settings for your phone number. When this number is called, your assistant will automatically answer.

Make your first calls

1

Test inbound calling

Call the phone number you just created. Your assistant will pick up and start the conversation with your configured first message.

2

Try outbound calling

Using the Dashboard:

In the dashboard, go to the outbound calls section:

1. Enter your own phone number as the target
2. Select your assistant
3. Click “Make Call”

Using the SDK:

TypeScript (Server SDK)

Python (Server SDK)

cURL

1
async function makeOutboundCall(assistantId: string, phoneNumber: string) {
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  try {
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    const call = await vapi.calls.create({
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      assistant: {
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        assistantId: assistantId,
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      },
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      phoneNumberId: 'your-phone-number-id', // Your Vapi phone number ID
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      customer: {
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        number: phoneNumber, // Target phone number
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      },
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    });
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    console.log('Outbound call initiated:', call.id);
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    return call;
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  } catch (error) {
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    console.error('Error making outbound call:', error);
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    throw error;
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  }
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}
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// Make a call to your own number for testing
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makeOutboundCall('your-assistant-id', '+1234567890');

Your assistant will call the specified number immediately.

3

Test web calling (optional)

You can also test your assistant directly in the dashboard by clicking the call button—no phone number required.

Next steps

Now that you have a working voice assistant:

• Customize the conversation: Update the system prompt to match your use case
• Add tools: Connect your assistant to external APIs and databases
• Configure models: Try different speech and language models for better performance
• Scale with APIs: Use Vapi’s REST API to create assistants programmatically