What Is an AI Call Agent
An AI Call Agent is an intelligent voice assistant that can talk, listen, and act like a trained human representative. It answers or makes calls automatically. It greets callers, understands what they need, and takes action. Agents handle real conversations 24/7. They reduce missed calls and free your team from repetitive phone work. They sound natural, follow your instructions, and can speak multiple languages.Answer calls
Pick up every incoming call, day or night, and resolve common questions.
Make calls
Call your contacts automatically with outbound campaigns.
Book appointments
Check availability and book meetings directly in your calendar.
Transfer to a person
Hand the call to your team when a human is needed.
Connecting a Phone Number
Every agent needs a phone number to make or receive calls. Go to Numbers and click + Add Number. You have several options:Purchase Number
Buy a new number directly in your Callin.io workspace.
Import from Twilio
Bring the numbers you already own in Twilio.
Add Telnyx Number
Import your Telnyx numbers once Telnyx is connected.
Add Personal Number
Verify a number you already use, such as your business line.
Tip: Learn every option step by step in Numbers And BYOC.
Understanding Call Usage and Costs
Each call uses two types of minutes:- Carrier minutes: charged by the phone provider (Twilio, Telnyx, or your own carrier) for the phone connection.
- Callin AI minutes: cover the AI that listens, thinks, and responds during the call.
Example: a 5-minute call = 5 carrier minutes + 5 Callin AI minutes.
Important: Calls made with numbers bought through Callin.io and our carrier have a 1-minute minimum charge. A 20-second call is billed as 1 minute. After the first minute, you pay the actual duration. This rule does not apply to browser test calls, imported numbers (Twilio or Telnyx), or your own SIP trunk.You can check your total minutes on Home (Total Usage). To see your plan or add credits, open Upgrade Plan.
Integrations and Webhooks
Your AI Call Agent doesn’t have to work alone. It connects to the tools you already use for scheduling, CRM, and automation. You’ll find them all in Actions in the sidebar. Many integrations use webhooks: simple URLs that receive data from each call in real time. A webhook sends structured information to any system that can receive HTTP requests, such as caller details, extracted data, timestamps, or transcripts.Why It Matters
Integrations open the door to thousands of tools:Google Calendar
Let your agent check availability and book appointments.
Make
Build automated scenarios without code.
Zapier
Connect your calls to Google Sheets, Slack, HubSpot, and more.
n8n
Create custom workflows triggered by call events.
- Send a Slack message after every missed call.
- Create a new CRM lead with the caller’s info and transcript.
- Send a follow-up email when an appointment is booked.
What to Do Next
You now know what AI Call Agents are, how they get a phone number, how calls are charged, and how they connect to your tools. Follow these steps to launch your first agent:1
Create your agent
Start from scratch or from a template, and write its instructions. See AI Agents.
2
Add a knowledge base
Give your agent your documents and FAQs so it answers with your information. See Knowledge Base.
3
Connect tools
Let your agent book meetings, transfer calls, or send data to your apps. See Tools.
4
Assign a phone number
Connect a number so your agent can make and receive calls. See Numbers And BYOC.
5
Start calling
Receive calls or launch an outbound campaign to your contacts. See Campaigns.
Create your first agent
Open Callin.io and start building now.