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

# Book Calendar

> Let your agent book appointments directly through Cal.com during a call.

## Overview

The Book Calendar tool connects your agent to Cal.com so it can confirm and book appointments in real time after the caller selects a time slot.

***

## Setup

<Steps>
  <Step title="Create a Cal.com account">
    Sign up at [cal.com](https://cal.com) if you don't have one.
  </Step>

  <Step title="Configure an event type">
    In your Cal.com dashboard, set up the event type you want bookings created under.
  </Step>

  <Step title="Collect your credentials">
    | Credential    | Where to find it                        |
    | ------------- | --------------------------------------- |
    | Event Type ID | The numeric ID in your event type's URL |
    | API Key       | Settings → Developer → API Keys         |
  </Step>

  <Step title="Add the function in UponAI">
    In your agent's Functions section, click **+ Add** and select **Book Calendar Appointment**.

    <Frame>
      <img src="https://mintcdn.com/uponai/7QzWw_-VPReC-RSK/images/screenshots/image11.png?fit=max&auto=format&n=7QzWw_-VPReC-RSK&q=85&s=830f82b68db2e8c31d5890930d56eb36" alt="Functions Add menu with Book Calendar Appointment highlighted" width="380" height="396" data-path="images/screenshots/image11.png" />
    </Frame>

    Enter:

    * Tool name
    * Cal.com API Key
    * Event Type ID
    * Tool description
    * Timezone (optional)
  </Step>

  <Step title="Update your prompt">
    Tell the agent when to book:

    ```txt theme={null}
    When the user selects a slot, book the appointment by calling the book_appointment function.
    ```
  </Step>
</Steps>

<Tip>
  Pair this with the **Check Calendar Availability** tool so your agent first checks open slots before confirming a booking.
</Tip>