An AI phone agent for the numbers you already own

Most writing about AI phone agents is about the voice: how natural it sounds, how fast it replies. Those things matter, but once the agent is live, the questions you deal with are about the line itself. Whose account are the numbers in? What happens when twenty people call during a sale? Where does a call go when the caller needs a person? This page is about those questions, because they decide whether an AI phone assistant makes your customer line calmer or just different.

Start with ownership. Asyntai answers numbers that live in your own Twilio account. You buy and keep the numbers in Twilio, Twilio bills you directly for the numbers and call minutes, and Asyntai connects with your Account SID and Auth Token. It lists the voice-capable numbers on the account, and when you press Import next to one, it sets that number's voice webhook so calls reach the agent. That arrangement keeps the phone side in your hands. If you add a seasonal number, remove an old one or move a number elsewhere, you do it in an account you control. To connect, you need an Asyntai Standard plan or higher and a paid Twilio account with at least one voice-capable number. In some countries Twilio asks for business verification before a new account can buy numbers, so it helps to start that step early.

Next comes the question of which number customers dial. Many stores already print a number on invoices, packaging and the contact page. You can keep it. Most phone providers offer call forwarding, so you can send calls from the existing line to the Twilio number when nobody answers, or after your opening hours. Your team still takes the calls it can, and the agent takes the rest. Or you can publish the Twilio number as the customer line and let the agent answer every call first.

On a normal day, many calls to an online store are about three things: where an order is, how returns work, and whether something is in stock or coming back. Returns and delivery are policy questions, and the agent answers them from your website and the documents you upload. Order status needs live data. If your order system has an API, a Custom Tool lets the agent ask the caller for the order number, call your endpoint, and read out the result. You set up the tool in a form in the Asyntai dashboard; your system only needs an endpoint that already returns the order data. An instruction in plain English makes the flow smoother: tell the agent to ask for the order number first, and to offer a transfer to your team when a caller has a problem with a delivery.

Busy days are where an AI phone agent proves itself. Your plan sets how many calls the agent answers at the same time: 5 on Standard and 10 on Pro. Within that limit, nobody waits for the first caller to finish. When every line is in use, the next caller hears that the lines are busy and is asked to call again in a few minutes. It is a clear message rather than endless ringing, and every caller within the limit talks to the agent from the first word.

Transfers deserve the same attention. Each imported number can have a transfer number, a desk phone or a mobile in international format. When a caller asks for a person during your escalation hours, the agent says it is putting them through. The phone that rings shows the caller's own number, so your team can see who it is. If nobody answers within 20 seconds, or the line is busy, the caller comes back to the agent, which apologizes and takes a callback request. Twilio bills the transferred leg as a normal outgoing call. Outside your hours, a caller who wants a person gets a callback request directly, with the number read back digit by digit and confirmed.

Then there are voice minutes. Standard includes 200 a month and Pro includes 1,500. Each answer the agent gives also counts as one AI reply on your plan, as it does in the website chat. When the month's minutes are used up, calls are declined with a short message until the minutes reset, so it is worth checking your call volume before you choose a plan. A simple way to size it: count the calls on your line in a normal month, multiply by the length of a typical call, and compare the total with the two allowances. Conversations through the voice button in your website chat use the same minutes, so include them if you plan to switch that on. For a breakdown of the monthly bill, see what an AI receptionist costs to run.

Finally, every call is saved as a conversation in your dashboard with the full transcript. That record is useful in two ways. When a transferred caller reaches your team, the conversation so far is already there. And over a month, the transcripts show you which questions your store pages leave open, which products people call about, and which calls really needed a person. Phone numbers and email addresses that callers give can also be saved as leads when lead collection is on, which suits wholesale or bulk-order enquiries that arrive by phone.

The Twilio voice setup guide covers each step in detail. In short: add your store website, write a greeting, test the agent in your browser with a real order number, connect Twilio, import the numbers, set the transfer numbers and hours, and call each line yourself. From then on your customer line answers every call it can, and hands the rest to your team.