AI receptionist API for phone appointment booking
For clinics, salons, workshops and any business that takes bookings by phone: an agent on your existing number answers, offers the hours and slot lengths you gave it, and creates the appointment. You pay per second of the call from a prepaid balance; the phone line is your own trunk at carrier cost.
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How do you build an AI appointment-booking agent with Wixzel Voice?
- 01POST /v1/sip-trunks
Connect the trunk your number already lives on and point its inbound route at the platform.
- 02POST /v1/agents
Create the receptionist: a prompt with your services, the hours and slot lengths it may offer, and a voice engine.
- 03GET /v1/appointments
Each booking the agent makes is an appointment you can list, read and cancel through the API.
- 04GET /v1/calls/{id}
Read the status and transcript of every call, and delete the ones you do not need to keep.
Which voice engine fits appointment booking?
Use the classic engine on Wixzel Voice, at $0.0867 per connected minute. English bookings need accurate names and dates; Nova-3 transcription with GPT-4o-mini is the cheapest reliable pairing. Switch the stt language for other languages, or the sarvam engine for Indian ones.
What does appointment booking cost on Wixzel Voice?
Wixzel Voice engine time for 3-minute calls on the classic engine, at typical speech rates, billed per second of actual usage. Telephony is your own trunk at your carrier’s rate and is not included, and shorter calls cost proportionally less.
| Calls per month | Connected minutes | Engine cost per month |
|---|---|---|
| 200 | 600 | $52.02 |
| 1,000 | 3,000 | $260 |
| 5,000 | 15,000 | $1,301 |
Prepaid: add credit from $5 and the calls spend it. Estimate your own mix.
Which guides show how to build an AI appointment-booking agent on Wixzel Voice?
Answer your existing Twilio number with an AI receptionist that books appointments, using a Twilio Elastic SIP trunk and the Wixzel Voice TypeScript SDK.
Four requests to a ringing phone, what a call record returns, and what a call costs.
Twilio, Telnyx, Plivo, Vonage, Bandwidth, Exotel, Vobiz or any SIP provider: what to set at the carrier.
Frequently asked questions
- Can a Wixzel Voice agent book appointments over the phone?
- Yes. An agent created with POST /v1/agents is told in its prompt which hours and slot lengths it may offer, and books into the appointments resource during the call. The booking is readable through GET /v1/appointments as soon as the call ends.
- Can the agent answer calls on my existing phone number?
- Yes, if that number is on a SIP trunk you can route. Point the trunk's origination URI at the platform and inbound calls reach the agent. Wixzel Voice does not port or sell numbers.
- What does a three-minute booking call cost?
- About 0.260 dollars on the classic engine, plus your carrier's per-minute rate for the trunk. The meter charges per second, so a shorter call costs proportionally less.
- Can the agent hand off to a person?
- Yes, on phone calls. List the numbers the agent may transfer to in its human_transfer settings; when a caller asks for a person, the agent bridges the call to one over your SIP trunk, and can hand the caller back if nobody answers. The transfer is blind: the agent does not brief the person first. Transfers are not available on test calls or in web and app sessions.
What else do developers build on Wixzel Voice?
Upload leads, start a campaign, and have an agent call each one over your own SIP trunk and ask your qualifying questions. Every call is a record with its status and transcript, linked to the lead.
Answer a support number with an agent that reads from a knowledge base you upload, handles the common questions, and leaves a transcript of every call.
Run phone agents in Indian languages on models built for them, with the sarvam engine covering speech-to-text, the language model and text-to-speech end to end.
Put an agent in a browser page, a Flutter app or a kiosk with no SIP trunk and no phone number: your server mints a one-minute session, the app streams audio over a WebSocket, and the session is billed like a call.
Connect Claude Code, claude.ai, Claude Desktop, Cursor or any MCP client to your account, and let an AI agent connect a carrier, build a voice agent, place calls, run campaigns and read transcripts, with every tool that spends money asking first.
Operator, prices, limits, refunds and data location, on one page.