Handle meeting no-shows via Gmail, Google Calendar, and OpenAI in n8n

Embed three buttons in reminder emails so attendees can confirm, reschedule, or cancel with one click

Who

Operators or admins who want to reduce no-shows and let attendees self-manage meetings

You get

Attendees click a button to confirm, reschedule, or cancel; the calendar updates automatically and a notification email is sent

You need

n8n · webhook · gmail · google-calendar · openai

Steps

1. Receive and route the request

   Configure a Webhook node in n8n (path: meeting-reschedule) to receive GET requests from reminder-email buttons. Links must include query parameters: action (confirm/reschedule/cancel), email, eventId, and newDateTime for reschedules. Use a Switch node to route to one of three branches based on the action value.

2. Configure credentials and global replacements

   Add credentials in n8n: Google Calendar OAuth2 (with access to the target calendar), Gmail (send permission), and OpenAI API. Then replace every YOUR_CALENDAR_ID in all Google Calendar nodes with your target calendar ID, and replace YOUR_TIMEZONE in the AI Agent node and the Create new event tool description with your timezone (e.g., Europe/London).

3. Confirm or cancel a meeting

   Confirm branch: use a Google Calendar node to get the event by eventId, extract the attendee email and hangoutLink (Google Meet), then send a confirmation email via Gmail. Cancel branch: get the event, delete it from the calendar, then send a cancellation email. Edit email bodies in the respective Gmail nodes to match your branding.

4. Reschedule a meeting

   Reschedule branch: read newDateTime from the request, fetch the original event details, then pass to an AI Agent. The agent uses gpt-4o-mini and connects to two Google Calendar tool nodes: Create new event tool creates a replacement event with Google Meet enabled, and Delete old event tool removes the original only after successful creation. Finally, send a reschedule notification via Gmail with the new time and meeting link.

   Execution prompt · Source text。AI Agent node (Move the meeting) text/prompt field

   Copy prompt

   You are a smart meeting assistant connected to Google Calendar.
   
   A user has requested to reschedule their meeting. Use the provided input to:
   - First create the new event
   - Then delete the old one using eventId
   
   ---
   
   ### Input (Dynamic JSON from user):
   ```json
   {{ $json }}
   Your Tasks:
   Extract the following from the input:
   
   email: the attendee's email
   
   eventId: the ID of the old event to delete
   
   newDateTime: time range (e.g. "06:00 PM – 07:00 PM")
   
   meetingDate: the date for the rescheduled event (format: YYYY-MM-DD)
   
   If meetingDate is not provided, use today’s date.
   
   Parse the newDateTime:
   
   Format: "hh:mm AM/PM – hh:mm AM/PM"
   
   Combine with meetingDate
   
   Time zone: YOUR_TIMEZONE
   
   Convert both start and end to UTC ISO 8601
   
   Create a new calendar event:
   
   Summary: "Rescheduled Meeting"
   
   Attendee: use the provided email
   
   Start and End time: use the parsed UTC values
   
   Enable Google Meet (hangoutLink)
   
    After the new event is successfully created, delete the old event using:
   
   calendar.deleteEvent
   
   Use the original eventId from the input

5. Build email links and activate

   Copy the production webhook URL and build three button links in your reminder email template: action=confirm, action=reschedule (with newDateTime), and action=cancel, all including email and eventId. Activate the workflow, then test each branch to verify calendar updates and email delivery. [First-test safety] Before the first test, disconnect the Gmail send and Google Calendar delete nodes, or use a test calendar and test inbox; reconnect only after branch logic looks correct.

Please set up the n8n workflow as follows:
1. Import the template or rebuild the node structure from workflow.json;
2. Configure the Webhook path as meeting-reschedule with responseMode lastNode;
3. Add Google Calendar OAuth2, Gmail, and OpenAI API credentials;
4. Globally replace YOUR_CALENDAR_ID and YOUR_TIMEZONE;
5. Configure Set field mappings and Switch branch conditions per the source node parameters;
6. Paste the above English prompt into the AI Agent node (do not change variable names);
7. Test all three query-parameter combinations: confirm, reschedule, and cancel.