Cal.com Booking

Automated Scheduling: The Call Booking function allows your AI agents to book appointments directly in your Cal.com calendar during conversations, streamlining the scheduling process from inquiry to confirmation.

Interactive Demo

See how to set up the Call Booking function for both simple agents and workflow agents:

Simple Agent Demo
Workflow Agent Demo

Overview

The Call Booking function integrates your Cal.com calendars with your AI agents, enabling them to book appointments automatically during conversations. This powerful feature completes the scheduling process by not just checking availability, but actually creating confirmed bookings. Key Benefits:

Book appointments automatically during conversations
Eliminate back-and-forth scheduling coordination
Reduce no-shows with instant calendar confirmations
Seamlessly integrate with your existing Cal.com setup

Integration: This function uses Cal.com, a popular open-source scheduling platform.

Prerequisites: You need a Cal.com account to use this function. Sign up at cal.com if you haven’t already.

Setup Instructions

Simple Agents
Workflow Agents

Add Call Booking to Simple Agents

Follow these steps to add the Call Booking function to your AI voice agent:

Step 1: Navigate to Simple Agents

From your dashboard sidebar, click on Simple Agents.

Step 2: Select Your Agent

Click on the agent you want to configure from the list.

Step 3: Open Custom Functions Tab

Click on the Custom Functions tab in the agent configuration.

Step 4: Add New Function

Click the Add Function button to open the function selection menu.

Step 5: Select Call Booking

Click on Call Booking from the available functions. A configuration popup will appear with two setup modes.

Configuration Modes for Simple Agents

Cal.com offers two ways to connect your calendar: Static Mode (no API key required) and Webhook Mode (requires API key for more control). Choose the mode that best fits your needs.

Static Mode
Webhook Mode

Static Mode Configuration

Static mode fetches publicly available event types using your Cal.com username or organization slug. This is the easiest way to get started and doesn’t require an API key.

Step 1: Enter Cal.com Username or Organization Slug

Enter your Cal.com username or organization slug:

Username: Your personal Cal.com username (e.g., jane if your Cal.com URL is cal.com/jane)
- Find it in your Cal.com profile settings
Organization Slug: Your organization’s Cal.com slug (e.g., acme if your team URLs are like acme.cal.com/jane or schedule.acme.com/jane)
- Find it in your organization settings

Step 2: Fetch Event Types

Click the Fetch Event Types button to retrieve all publicly available event types from your Cal.com account.After fetching, you’ll see a dropdown list of all your available event types (e.g., “30 Minute Meeting”, “Discovery Call”, “Consultation”).Choose an Event Type from the dropdown that you want your AI agent to book appointments for.Click Next to continue.

Step 3: Configure Function Options

Configure the following options:

Function Name

Give your function a descriptive name in snake_case (e.g., book_consultation, schedule_meeting, book_appointment).

Description

Describe when this function should be used. This helps the AI understand when to book appointments.Examples:

“Use this when the customer wants to book a consultation appointment”
“Book this when the customer confirms they want to schedule a meeting”
“Use this to create an appointment booking in the calendar”

Timezone (Optional)

Specify the timezone for booking appointments (e.g., America/New_York or Europe/London). If not provided, Cal.com will use its default timezone (UTC).

Step 4: Create Function

Click Create Function to save your configuration. The function is now ready to use!

Step 5: Test the Function

Test your newly created function:

Start a call or conversation with your AI agent
Ask your agent to book an appointment, for example:
- “I’d like to book an appointment for Tuesday at 2 PM”
- “Can you schedule me for next Monday at 10 AM?”
- “Book me for the 3 PM slot on Thursday”

Your agent will use the function to create a booking in your Cal.com calendar and confirm the appointment with the customer.

Static mode uses public event types, so ensure the event type you selected is set to “Public” in your Cal.com settings.

Webhook Mode Configuration

Webhook mode provides more control and security by using your Cal.com API key. This allows you to access private event types and configure advanced settings.

Step 1: Enter Cal.com API Key and Event Type ID

You’ll need two pieces of information from your Cal.com account:

Cal.com API Key

Generate an API key from your Cal.com account:

Log in to Cal.com
Navigate to Settings → Security → API Keys
Click New API Key
Give it a name (e.g., “OpenMic Integration”)
Copy the generated API key
Paste it in the API Key field

Keep your API key secure: Never share your API key publicly. It provides access to your Cal.com account and calendar data.

Cal.com Event Type ID

Find your Event Type ID:

Go to your Cal.com dashboard
Click on Event Types
Open the event type you want to use
Look at the URL in your browser’s address bar
The Event Type ID is the number between the slashes
- Example: app.cal.com/event-types/123456 → Event Type ID is 123456

For more details, see Cal.com’s guide on finding Event Type IDs.

Configure Additional Fields

After entering your API key and Event Type ID, you’ll see additional webhook configuration options:Call a webhook before running this tool (Optional)

Toggle this on to validate or enrich data before booking appointments
Use the pre-call webhook URL: Use the webhook URL configured in your agent settings
Custom webhook URL: Or provide a custom webhook URL for this specific function (e.g., https://your-domain.com/webhook/pre-tool)

Click Next to proceed to the function configuration.

Step 2: Configure Function Options

Configure the following options:

Function Name

Give your function a descriptive name in snake_case (e.g., book_private_meeting, schedule_team_call, book_consultation).

Description

Describe when this function should be used. This helps the AI understand when to book appointments.Examples:

“Use this when the customer confirms they want to book a consultation”
“Book this when someone wants to schedule a private meeting”
“Use this to create confirmed appointment bookings”

Step 3: Create Function

Click Create Function to save your configuration. The function is now ready to use!

Step 4: Test the Function

Test your newly created function:

Start a call or conversation with your AI agent
Ask your agent to book an appointment, for example:
- “I’d like to book an appointment for Tuesday at 2 PM”
- “Can you schedule me for next Monday at 10 AM?”
- “Book me for the 3 PM slot on Thursday”

Your agent will use the function to create a booking in your Cal.com calendar and confirm the appointment with the customer.

Webhook mode works with both public and private event types, giving you more flexibility in your scheduling setup.

Agent Prompt Example

To help your AI agent use the booking function effectively, add clear instructions to your agent’s system prompt:

When customers want to book an appointment and have chosen a specific time slot, 
use the book_appointment function to create the booking in the calendar.

Always confirm the following details before booking:
- Preferred date and time
- Customer's name
- Customer's email address
- Any special requirements or notes

After successfully booking, provide the customer with:
- Confirmation of the booked date and time
- Timezone information
- Any preparation instructions or next steps

Example conversation flow:

Customer: "I'd like to book the Tuesday 2 PM slot"
Agent: "Perfect! Let me book that for you on Tuesday at 2 PM. May I have your 
name and email address to confirm the appointment?"

Customer: "It's John Smith, john@example.com"
Agent: [Uses booking function] "Great! I've confirmed your appointment for 
Tuesday, March 14th at 2:00 PM Eastern Time. You'll receive a confirmation 
email at john@example.com with all the details."

Add Call Booking to Workflow Agents

Workflow agents allow you to create sophisticated multi-step processes. Follow these steps to add Call Booking to your workflow:

Step 1: Navigate to Workflow Agents

From your dashboard sidebar, click on Workflow Agents.

Step 2: Select Your Workflow

Click on the workflow you want to configure from the list.

Step 3: Open the Workflow Editor

In the workflow editor, click the + Add Node button to add a new node to your workflow.

Step 4: Choose Cal.com Booking

Select Cal.com Booking from the available node types. The node will be added to your workflow canvas.

Step 5: Configure the Booking Node

Click on the newly added Cal.com Booking node to open the configuration panel. A configuration popup will appear with two setup modes.

Configuration Modes for Workflow Agents

The configuration process for workflow agents is the same as for simple agents. Choose between Static Mode and Webhook Mode based on your needs.

Static Mode
Webhook Mode

Static Mode Configuration

Static mode fetches publicly available event types using your Cal.com username or organization slug. This is the easiest way to get started and doesn’t require an API key.

Step 1: Enter Cal.com Username or Organization Slug

Enter your Cal.com username or organization slug:

Username: Your personal Cal.com username (e.g., jane if your Cal.com URL is cal.com/jane)
- Find it in your Cal.com profile settings
Organization Slug: Your organization’s Cal.com slug (e.g., acme if your team URLs are like acme.cal.com/jane or schedule.acme.com/jane)
- Find it in your organization settings

Step 2: Fetch Event Types

Static mode uses public event types, so ensure the event type you selected is set to “Public” in your Cal.com settings.

Webhook Mode Configuration

Webhook mode provides more control and security by using your Cal.com API key. This allows you to access private event types and configure advanced settings.

Step 1: Enter Cal.com API Key and Event Type ID

You’ll need two pieces of information from your Cal.com account:

Cal.com API Key

Generate an API key from your Cal.com account:

Log in to Cal.com
Navigate to Settings → Security → API Keys
Click New API Key
Give it a name (e.g., “OpenMic Workflow Integration”)
Copy the generated API key
Paste it in the API Key field

Keep your API key secure: Never share your API key publicly. It provides access to your Cal.com account and calendar data.

Cal.com Event Type ID

Find your Event Type ID:

Go to your Cal.com dashboard
Click on Event Types
Open the event type you want to use
Look at the URL in your browser’s address bar
The Event Type ID is the number between the slashes
- Example: app.cal.com/event-types/123456 → Event Type ID is 123456

For more details, see Cal.com’s guide on finding Event Type IDs.

Configure Additional Fields

After entering your API key and Event Type ID, you’ll see additional webhook configuration options:Call a webhook before running this tool (Optional)

Toggle this on to validate or enrich data before booking appointments
Use the pre-call webhook URL: Use the webhook URL configured in your workflow settings
Custom webhook URL: Or provide a custom webhook URL for this specific function (e.g., https://your-domain.com/webhook/pre-booking)

Webhook mode works with both public and private event types, giving you more flexibility in your workflow scheduling setup.

Connect the Node in Your Workflow

After configuring the node (see configuration options below), connect it to other nodes in your workflow by dragging connections between nodes. This determines when the booking function will be triggered in your workflow sequence.

Save Your Workflow

Once you’ve configured and connected the Cal.com Booking node, click the Save button to save your workflow changes.

Pro Tip: Combine with Check Calendar Availability

Best Practice: For the best user experience, combine the Call Booking function with the Check Calendar Availability function.This allows your agent to:

First check available time slots when customers ask “When are you available?”
Then book the appointment once the customer chooses a preferred time

This two-step approach reduces booking conflicts and provides a smoother scheduling experience.

Configuration Best Practices

Collect Required Information First

Ensure you have customer name and email before booking
Confirm the exact date and time
Verify timezone if dealing with customers in different regions
Ask about any special requirements

Write Clear Function Descriptions

Be specific about when to trigger (e.g., “when customer confirms booking”)
Mention the type of appointment or meeting
Include any prerequisites for booking

Test Your Function Thoroughly

Test with your own email first
Try booking different time slots
Verify confirmation emails are sent
Check that bookings appear in your Cal.com calendar

Handle Timezones Carefully

Always specify timezone in the configuration
Train your agent to confirm timezone with customers
Mention timezone when confirming bookings

Error Handling

Train your agent to handle booking conflicts gracefully
Provide alternative times if preferred slot is unavailable
Have a fallback process for failed bookings

Use Cases and Examples

Sales Consultation Booking

Scenario: Sales agent books consultation calls automaticallyConfiguration:

Mode: Static or Webhook
Event Type: “30 Minute Sales Consultation”
Description: “Use this when prospects confirm they want to book a consultation”

Agent Interaction:

Customer: "I'd like to schedule a consultation for Tuesday at 2 PM."
Agent: "Excellent choice! Let me get some details to book that for you. 
May I have your full name and email address?"
Customer: "Sarah Johnson, sarah.j@company.com"
Agent: [Uses booking function] "Perfect! I've booked your consultation for 
Tuesday, March 14th at 2:00 PM EST. You'll receive a confirmation email at 
sarah.j@company.com with a calendar invite and meeting link. Looking forward 
to speaking with you!"

Medical Appointment Booking

Scenario: Healthcare practice books patient appointmentsConfiguration:

Mode: Webhook (for private scheduling)
Event Type: “Doctor Appointment”
Description: “Use this when patients confirm they want to book an appointment”

Agent Interaction:

Patient: "I'd like to book the Monday 9 AM slot with Dr. Smith."
Agent: "I'd be happy to book that appointment for you. May I please have 
your full name, date of birth, and email address?"
Patient: "Michael Brown, January 15, 1980, michael.brown@email.com"
Agent: [Uses booking function] "Thank you, Michael. I've confirmed your 
appointment with Dr. Smith for Monday, March 13th at 9:00 AM. You'll receive 
a confirmation email with pre-appointment instructions. Please arrive 10 minutes 
early to complete any necessary paperwork."

Service Appointment Booking

Scenario: Service business books on-site visitsConfiguration:

Mode: Static
Event Type: “On-site Service Call”
Description: “Use when customers confirm they want to book a service appointment”

Agent Interaction:

Customer: "Yes, I'll take the Thursday 1 PM slot for the HVAC inspection."
Agent: "Great! Let me book that for you. I'll need your name, address, and 
email address please."
Customer: "Tom Wilson, 123 Main St, Anytown, tom.w@email.com"
Agent: [Uses booking function] "Perfect! I've scheduled your HVAC inspection 
for Thursday, March 16th at 1:00 PM at 123 Main St. Our technician will arrive 
within a 30-minute window. You'll receive a confirmation email at tom.w@email.com 
and a reminder text 24 hours before the appointment."

Interview Scheduling

Scenario: Recruiting team books candidate interviewsConfiguration:

Mode: Webhook
Event Type: “Candidate Interview - 45 min”
Description: “Use when candidates confirm they want to schedule an interview”

Agent Interaction:

Candidate: "Wednesday at 2 PM works perfect for me."
Agent: "Wonderful! Let me get that scheduled for you. Please confirm your 
full name and the best email address to send the interview details to."
Candidate: "Emily Chen, emily.chen@email.com"
Agent: [Uses booking function] "Excellent! I've scheduled your interview for 
Wednesday, March 15th at 2:00 PM PST. You'll receive a confirmation email at 
emily.chen@email.com with the video call link and information about the 
interview format. We're looking forward to meeting you!"

Difference: Static vs Webhook Mode

Static Mode

Advantages:

No API key required
Quick and easy setup
Perfect for public event types
Minimal configuration needed

Best For:

Simple booking needs
Public-facing scheduling
Getting started quickly
Single-user calendars

Webhook Mode

Advantages:

Access to private event types
More configuration options
Enhanced security
Advanced features (custom fields, webhooks)

Best For:

Private/internal scheduling
Advanced configuration needs
Team calendars
Enterprise use cases

Frequently Asked Questions

Do I need a Cal.com account?

Yes, you need a Cal.com account to use this function. Cal.com offers both free and paid plans. You can sign up at cal.com.

What's the difference between Static and Webhook mode?

Static mode fetches publicly available event types using your username/organization slug and requires no API key. Webhook mode uses your Cal.com API key for access to private event types and more advanced configuration options.

How do I find my Event Type ID?

Go to Cal.com and open your Event Types
Click on the event type you want to use
Look at the URL in your browser’s address bar
The Event Type ID is the number between the slashes (e.g., app.cal.com/event-types/123456)

For more details, see Cal.com’s official guide.

Can I book multiple event types?

Yes! Create multiple Call Booking functions, one for each event type. Give each function a clear name and description so your AI agent knows which one to use for different scenarios.

What information is required to book an appointment?

The basic requirements are:

Customer name
Customer email address
Desired date and time

Additional information may be required depending on your Cal.com event type configuration (phone number, custom questions, etc.).

Will customers receive confirmation emails?

Yes! When an appointment is booked through this function, Cal.com automatically sends confirmation emails to the customer with calendar invites and meeting details.

Can I cancel or reschedule bookings?

Bookings created through this function are standard Cal.com appointments. Customers can cancel or reschedule using the links in their confirmation emails, or you can manage them directly in your Cal.com dashboard.

How do I handle booking conflicts?

Train your agent to check availability first using the Check Calendar Availability function before booking. If a booking fails due to a conflict, your agent should offer alternative times to the customer.

Can I edit the function after creating it?

Yes, you can edit the function configuration at any time. Go to the Custom Functions tab in your agent settings and edit the function as needed.

Does this work with team event types?

Yes! Both Static and Webhook modes support team event types. Just make sure to use the correct organization slug (Static mode) or Event Type ID (Webhook mode) for your team event.

Troubleshooting

Unable to fetch event types (Static Mode)

Possible causes:

Incorrect username or organization slug
Event types are set to private in Cal.com
Network connectivity issues

Solutions:

Verify your Cal.com username/organization slug is correct
Ensure your event types are set to “Public” in Cal.com settings
Check your internet connection
Try refreshing the page and fetching again

API authentication failed (Webhook Mode)

Possible causes:

Invalid API key
API key was revoked or expired
Incorrect Event Type ID

Solutions:

Double-check your API key is copied correctly
Generate a new API key in Cal.com settings
Verify the Event Type ID is correct (check the URL in Cal.com)
Ensure the API key has the necessary permissions

Booking fails during conversation

Possible causes:

Time slot no longer available
Missing required information (name, email)
Timezone mismatch
Event type settings issue

Solutions:

Check availability before booking
Ensure all required fields are collected
Verify timezone settings in both function and Cal.com
Review event type configuration in Cal.com

Customer not receiving confirmation emails

Possible causes:

Email address entered incorrectly
Cal.com email notifications disabled
Emails going to spam folder

Solutions:

Verify email address is correct
Check Cal.com notification settings
Ask customer to check spam/junk folder
Add Cal.com to safe senders list

Function not triggering during conversations

Possible causes:

Function description is unclear
Agent prompt doesn’t instruct AI to use the function
Missing customer confirmation

Solutions:

Update the function description to be more specific
Add clear instructions to your agent’s system prompt
Train agent to get explicit booking confirmation from customer
Review the function execution logs

Need Help?

If you encounter issues or have questions about the Call Booking function:

Test with your own email first to verify setup
Review your function description and agent prompt
Check your Cal.com event type settings and availability
Verify API key permissions (webhook mode)
Review function execution logs in your dashboard
Ensure all required customer information is collected

For technical support or questions about Cal.com integration, contact our support team.

​Interactive Demo

​Overview

​Setup Instructions

​Add Call Booking to Simple Agents

​Step 1: Navigate to Simple Agents

​Step 2: Select Your Agent

​Step 3: Open Custom Functions Tab

​Step 4: Add New Function

​Step 5: Select Call Booking

​Configuration Modes for Simple Agents

​Static Mode Configuration

​Step 1: Enter Cal.com Username or Organization Slug

​Step 2: Fetch Event Types

​Step 3: Configure Function Options

​Function Name

​Description

​Timezone (Optional)

​Step 4: Create Function

​Step 5: Test the Function

​Webhook Mode Configuration

​Step 1: Enter Cal.com API Key and Event Type ID

​Cal.com API Key

​Cal.com Event Type ID

​Configure Additional Fields

​Step 2: Configure Function Options

​Function Name

​Description

​Step 3: Create Function

​Step 4: Test the Function

​Agent Prompt Example

​Add Call Booking to Workflow Agents

​Step 1: Navigate to Workflow Agents

​Step 2: Select Your Workflow

​Step 3: Open the Workflow Editor

​Step 4: Choose Cal.com Booking

​Step 5: Configure the Booking Node

​Configuration Modes for Workflow Agents

​Static Mode Configuration

​Step 1: Enter Cal.com Username or Organization Slug

​Step 2: Fetch Event Types

​Webhook Mode Configuration

​Step 1: Enter Cal.com API Key and Event Type ID

​Cal.com API Key

​Cal.com Event Type ID

​Configure Additional Fields

​Connect the Node in Your Workflow

​Save Your Workflow

​Pro Tip: Combine with Check Calendar Availability

​Configuration Best Practices

​Use Cases and Examples

​Difference: Static vs Webhook Mode

Static Mode

Webhook Mode

​Frequently Asked Questions

​Troubleshooting

​Need Help?

Interactive Demo

Overview

Setup Instructions

Add Call Booking to Simple Agents

Step 1: Navigate to Simple Agents

Step 2: Select Your Agent

Step 3: Open Custom Functions Tab

Step 4: Add New Function

Step 5: Select Call Booking

Configuration Modes for Simple Agents

Static Mode Configuration

Step 1: Enter Cal.com Username or Organization Slug

Step 2: Fetch Event Types

Step 3: Configure Function Options

Function Name

Description

Timezone (Optional)

Step 4: Create Function

Step 5: Test the Function

Webhook Mode Configuration

Step 1: Enter Cal.com API Key and Event Type ID

Cal.com API Key

Cal.com Event Type ID

Configure Additional Fields

Step 2: Configure Function Options

Function Name

Description

Step 3: Create Function

Step 4: Test the Function

Agent Prompt Example

Add Call Booking to Workflow Agents

Step 1: Navigate to Workflow Agents

Step 2: Select Your Workflow

Step 3: Open the Workflow Editor

Step 4: Choose Cal.com Booking

Step 5: Configure the Booking Node

Configuration Modes for Workflow Agents

Static Mode Configuration

Step 1: Enter Cal.com Username or Organization Slug

Step 2: Fetch Event Types

Webhook Mode Configuration

Step 1: Enter Cal.com API Key and Event Type ID

Cal.com API Key

Cal.com Event Type ID

Configure Additional Fields

Connect the Node in Your Workflow

Save Your Workflow

Pro Tip: Combine with Check Calendar Availability

Configuration Best Practices

Use Cases and Examples

Difference: Static vs Webhook Mode

Frequently Asked Questions

Troubleshooting

Need Help?