WhatsApp appointment booking.
Free, by chat or call.

Clinics, salons, tutors, and consultants get most booking requests on WhatsApp already. The work is in the back-and-forth: “Do you have anything Thursday?”, “What does a cleaning cost?”, “Is Dr. Mehta in on Saturday?” An AI chat agent can handle all of that. How it then makes the booking is your choice:

Start with the simplest one that fits. You can move up later without changing the agent’s knowledge base, just its instructions and tools.

If you already use a scheduling page, such as Calendly, Cal.com, or Google Calendar’s appointment schedule, the agent’s job is to answer questions and hand over the link at the right moment:

1. Add your services, prices, durations, and preparation notes to a knowledge base in Wapzen.
2. Create a chat agent and add a line to its instructions: “When someone wants to book, answer their questions first, then send this link: [your booking page].”
3. Connect your number by QR code and pick the agent for it.

The scheduler shows only free slots, sends its own confirmation, and blocks double bookings. The downside is the extra step: some customers won’t leave the chat to fill in a form.

For a practice with a front desk, the agent can take the whole request in the chat and save it, and a person confirms the exact time. It suits businesses whose diary is on paper or in software without an API.

The sheet and script

Create a Google Sheet with a tab named Requests, open Extensions › Apps Script, and paste this. Change KEY, deploy it as a Web app (Execute as: Me, Who has access: Anyone), and copy the URL with ?key= and your key on the end.

// In your Bookings sheet: Extensions › Apps Script. Paste this, change KEY,
// then Deploy › New deployment › Web app (Execute as: Me, Who has access: Anyone).
const KEY = "replace-with-a-long-random-word";

function doPost(e) {
  if (e.parameter.key !== KEY) return reply({ ok: false, error: "wrong key" });
  const b = JSON.parse(e.postData.contents);
  SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Requests").appendRow(
    [new Date(), b.name, b.contact_number, b.service, b.preferred_day,
      b.preferred_time, b.notes || "", "To confirm"].map(safe));
  return reply({ ok: true });
}

// Customers type this text: never let it start a formula.
function safe(value) {
  return typeof value === "string" && /^[=+\-@]/.test(value) ? "'" + value : value;
}

function reply(data) {
  return ContentService.createTextOutput(JSON.stringify(data))
    .setMimeType(ContentService.MimeType.JSON);
}

The tool

In Wapzen, open Tools › Create Tool › API Request. Name it save_booking_request, describe it as “Save a confirmed booking request”, set the method to POST and the URL to your web app, and add these parameters:

The instructions

Then create a chat agent, attach your knowledge base and the tool, and adapt these instructions:

You are the WhatsApp assistant for [Clinic], a [dental clinic] in [area]. You answer questions about our services, prices, and timings, and take appointment requests.

Use only the information in your knowledge base. Never give medical advice: for pain, swelling, or emergencies, ask the patient to call [phone number].

To take a booking request:
1. Ask which service they need, and if they prefer a particular doctor.
2. Ask for a preferred day and time within our hours: [Mon–Sat, 10 am–7 pm].
3. Ask for their name and a contact number.
4. Repeat the request back and ask them to confirm.
5. After they confirm, use save_booking_request. Then say the front desk will confirm the exact time on WhatsApp within [2 working hours].

Rules: short replies, one question at a time. Never promise a slot yourself.

Each request lands in the sheet marked To confirm, with the time it came in, so your team can work out what “tomorrow” meant. Confirm it in the same WhatsApp chat.

The agent doesn’t see the customer’s WhatsApp number, so the instructions ask for one. It also doesn’t know today’s date, which is why it saves the day the way the customer said it.

If your booking software has an API, the agent can check the diary and book in the chat. You need two API Request tools:

• check_availability: GET your system’s availability endpoint, with a date parameter (“Requested day in YYYY-MM-DD form”). Description: “Look up free times. Use before offering any slot.”
• create_booking: POST to the booking endpoint, with the customer’s name, contact number, service, and the chosen slot exactly as check_availability returned it.

Put your API key in the tool’s Headers (for example Authorization); it’s stored with the tool and never shown to the agent. If your system has no API but connects to Zapier, Make, or n8n, put a webhook there in between.

Two details that make or break it

• Return today’s date. The agent doesn’t know what day it is, so “next Tuesday” needs an anchor. Have the availability response start with it:

Today is Tuesday 28 October 2026.
Free slots for cleaning (30 min):
Wed 29 Oct: 10:00, 11:30, 16:00
Thu 30 Oct: 12:00, 17:30

• Keep responses short. The agent reads the response before replying, and Wapzen passes on the first 3,000 characters. Return a short list of free times, not the whole calendar.

Some customers will always call. A Wapzen voice agent answers WhatsApp calls on the same number and can use the same tools, so it can save a request or book a slot out loud. Give it a Send Text tool too, and it messages the booking details to the caller during the call, so they have them in writing.

Voice agents speak dozens of languages: set the one most of your callers use. For a front-desk setup that answers every call, see AI receptionist.

Reminders cut no-shows, and there are three ways to send them:

• By hand, free. In the WhatsApp Business app, save the reminder as a quick reply and send it to the next day’s appointments each evening. Fine for ten a day, tedious for fifty.
• Template messages on the Business API. Booking software that connects to the API can send them automatically, as utility templates that Meta charges per message. See WhatsApp Business API pricing.
• Reminder calls with Wapzen. Create an outbound campaign with a voice agent that confirms the visit, and add the next day’s patients as leads when you want the calls to go out. Adding a lead places the call straight away, so add them by hand or let your automation tool do it at a set time through the API.

Know the limits of the third option: a lead carries a name and number, not the appointment, so the agent confirms “your appointment with us tomorrow” rather than reading out the time. Nobody answers? The lead is marked unsuccessful, and Wapzen doesn’t redial on its own. The same pattern is shown step by step in COD order confirmation calls.

Wapzen is an independent product, not made by Meta or WhatsApp. It links your number as a device. Message and call only people who expect to hear from you: WhatsApp restricts numbers that send unwanted messages or calls.