> ## Documentation Index
> Fetch the complete documentation index at: https://docs.assistable.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Choose a calendar and test appointment booking

> Assign one active calendar to an assistant and verify the appointment it creates.

An assistant has one active calendar assignment. Use that assignment for a single service or booking destination. Selecting another calendar replaces the previous one.

## Before you start

You need permission to edit the assistant and its calendar assignment. Create or connect the intended calendar in the same account first. For GoHighLevel calendars, confirm the account's [GHL connection](/v3/guides/ghl/connect).

## Assign and test the calendar

1. Open the assistant and its **Calendars** picker. Wait for the existing assignment to load.
2. Select the intended calendar. Check its name and provider before confirming the assignment. Clicking the currently assigned calendar removes it.
3. Open **Tool Kit** and attach `get_availability` and `book_appointment` if they are not assigned. Use [platform tools](/v3/platform-tools) for tool descriptions. Add contact-update or appointment-management tools only when your task needs them.
4. In the prompt, tell the assistant which service it books, to ask for the customer's timezone, to offer returned available times, and to confirm a booking only after a successful tool result.
5. Save your prompt and tool changes, then **Publish** before testing a live voice or customer channel. Run a conversation with a test contact and choose an available time with an explicit date and timezone.
6. Open the destination calendar. Verify one appointment with the correct contact, calendar, date, time, and timezone. Check any confirmation message separately.

A spoken or written promise is not a booking receipt. If the tool reports an unconfirmed result, inspect the calendar before repeating the request.

## More than one booking destination

For separate services, use separate assistants with their own calendar assignments when that matches your routing. A custom tool can implement more complex calendar selection, but that is a custom integration: it must resolve the right calendar, check availability, create the appointment, and return an explicit result. Adding calendar names to a prompt does not create multiple native assignments.

## If the test fails

* **No calendars appear:** check account selection and the provider connection. For GHL, verify authorization for the intended location.
* **Wrong calendar:** reopen the picker and check the saved assignment. Changing prompt text alone does not change the binding.
* **No available times:** compare provider availability, timezone, and booking rules for the same date.
* **Unconfirmed booking or timeout:** check existing appointments before retrying; the first request may still have created one.

Continue with [calendar troubleshooting](/v3/guides/troubleshooting/booking) if the tool result and calendar disagree.


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