Quickstart

Create your first AI-powered phone line that can make and receive calls

In this quickstart, you'll create an AI-powered phone line that can make and receive calls. By the end, you'll have a working phone number connected to your AI agent.

What you'll learn:

• Create your KrosAI account and API key

• Purchase a phone number

• Connect an AI endpoint (ElevenLabs, Vapi, or custom)

• Make your first inbound and outbound calls

Prerequisites

Before you begin, you'll need:

• A KrosAI account (sign up free)

• An AI voice provider account (ElevenLabs, Vapi, or Retell)

• A phone to test calls

1

Step 1: Create your account

• Go to cockpit.krosai.com

• Sign up with email or Google

• Complete KYC verification (required for phone numbers) - takes ~2 minutes

KYC verification is required by telecom regulations before purchasing phone numbers. We use Sumsub for secure identity verification.

2

Step 2: Create an API key

Using the Dashboard

• Navigate to Developers → API Keys

• Click Create API Key

• Name it (e.g., "My First Key")

• Select scopes:

  • numbers:read - View phone numbers

  • numbers:write - Purchase/configure numbers

  • calls:read - View call logs

  • calls:write - Make outbound calls

• Click Create

• Copy and save your key - it's only shown once!

Your API key will look like: kros_live_abc123...

3

Step 3: Purchase a phone number

TypeScript

 const response = await fetch('https://api.krosai.com/v1/phone-numbers', {
  method: 'POST',
  headers: {
    'x-api-key': 'kros_live_your_key_here',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    inventory_id: 'inv_ng_12345', // From GET /phone-numbers/available
  }),
});

const { number, id } = await response.json();
console.log('Purchased:', number); // [phone]

Python

cURL

Dashboard

4

Connect AI Agent Providers

5

Step 4: Create an endpoint

An endpoint defines where inbound calls are routed—typically your AI voice agent.

Vapi

// Create a Vapi endpoint:
const response = await fetch('https://api.krosai.com/v1/endpoints', {
  method: 'POST',
  headers: {
    'x-api-key': 'kros_live_your_key_here',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    name: 'My Support Agent',
    type: 'agent',
    url: 'sip:[email protected]', // Or your provider's SIP URI
    provider_config: {
      provider: 'vapi',
      assistant_id: 'asst_abc123',
    },
  }),
});

const { id: endpointId } = await response.json();

ElevenLabs

Dashboard

6

Step 5: Attach endpoint to phone number

TypeScript

await fetch(`https://api.krosai.com/v1/phone-numbers/${phoneNumberId}`, {
  method: 'PATCH',
  headers: {
    'x-api-key': 'kros_live_your_key_here',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    endpoint_id: endpointId,
    allow_inbound: true,
    allow_outbound: true,
  }),
});

Dashboard

7

Step 6: Make your first call

Test inbound call

Call your new phone number from any phone. Your AI agent will answer:

📞 Call: [phone] ↓ 🤖 Your AI agent answers and starts the conversation

Make an outbound call

TypeScript

const response = await fetch('https://api.krosai.com/v1/outbound-calls', {
  method: 'POST',
  headers: {
    'x-api-key': 'kros_live_your_key_here',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    from_number: '[phone]', // Your KrosAI number
    to_number: '[phone]',      // Destination phone
    endpoint_id: endpointId,        // Your AI agent
  }),
});

const { call_id, status } = await response.json();
console.log('Call initiated:', call_id);

Python

Using the Playground

The KrosAI Dashboard includes a Playground for testing calls without code:

• Go to Playground in the dashboard

• Select your phone number

• Enter a destination number

• Click Call

• Watch real-time call events and transcription

🎉 Congratulations!

You've successfully:

• ✅ Created a KrosAI account

• ✅ Purchased a phone number

• ✅ Connected an AI agent

• ✅ Made your first call

Next steps

Deep dive into integrations

• ElevenLabs Integration Guide - Voice cloning and natural conversations

• Vapi Integration Guide - Structured workflows and tool calling

• Retell Integration Guide - Low-latency enterprise deployments