Who is this for?
This workflow is for healthcare professionals, consultants, coaches, and service businesses who want to completely automate their appointment booking system via WhatsApp — without manual intervention for reservations, availability checks, or cancellation management.
What problem is this workflow solving? / Use case
Managing appointments manually via WhatsApp is extremely time-consuming: checking availability, confirmations, rescheduling, cancellations. This workflow automates the entire process — from initial request to final confirmation — allowing your clients to book, modify, or cancel appointments 24/7, in natural language, directly via WhatsApp.
What this workflow does
- Processes multi-modal messages (text, audio, images) from WhatsApp Business API
- Detects message type and routes to appropriate processing (Whisper for audio, GPT-4 Vision for images)
- Uses AI Agent with 5 Cal.com tools to manage complete appointment lifecycle
- Checks real-time availability in your Cal.com calendar
- Books appointments autonomously without human intervention
- Handles cancellations and rescheduling requests
- Maintains conversation context with Simple Memory for natural exchanges
- Formats responses with Unicode bold for better WhatsApp readability
- Sends automated replies directly to the client
The result: a fully automated 24/7 appointment management system via WhatsApp.
Setup
1. WhatsApp Business API
- Connect your WhatsApp Business API account in n8n.
- Set up the webhook in Facebook Developer Console (Webhook → Messages → Subscribe).
- Add your phone_number_id and access token credentials.
- Create a Cal.com account and configure your calendar.
- Generate an API Key from Cal.com settings.
- Set up your event types (duration, availability, pricing).
- Add your Cal.com API credentials in n8n.
3. OpenAI
- Get an OpenAI API key (for GPT-4, Whisper, and Vision).
- Add your OpenAI credentials in n8n.
- The workflow uses GPT-4 for conversation, Whisper for audio transcription, and GPT-4 Vision for image analysis.
4. Customize the AI Agent
- Edit the System Message to define your agent's personality, tone, and business context.
- Adjust timezone in tool parameters (default: Europe/Paris).
- Configure event type IDs for different appointment types.
5. Test & activate
- Test with different message types (text, audio, image) from WhatsApp.
- Verify appointments are created correctly in Cal.com.
- Switch to production mode and activate the workflow.
This workflow helps you build a fully autonomous AI booking assistant, transforming WhatsApp into a 24/7 appointment management system.
Need help customizing?
Contact me for consulting and support: LinkedIn / Youtube