Google Calendar Events with Gemini AI Follow-up Suggestions via WhatsApp & Email

Description

Who Is This For?
This n8n automation workflow is designed for sales teams, client managers, consultants, or anyone who regularly schedules and follows up on meetings — and wants to save time doing it.
If you often find yourself juggling between Google Sheets, Google Calendar, email, and WhatsApp just to manage your meetings, confirmations, and follow-ups — this workflow is for you.

What This Workflow Does
This workflow is structured into two main, independently scheduled branches:
1. Create Event (Schedule Meetings)
Trigger:** Starts automatically on a schedule (e.g., every minute).
Data Source:* Fetches new meeting data from a *Google Sheet**.
Event Creation:* Creates a new event in *Google Calendar** using the data.
Confirmation:* Sends a confirmation message via *WhatsApp (Rapiwa)* and *Email (Gmail)**.
Status Update:* Updates the source *Google Sheet** to mark the meeting as 'sent'.

2. Reminder Event (Schedule Follow-ups)
Trigger:** Starts automatically on a schedule (e.g., every minute).
Past Events:* Retrieves recent past events from *Google Calendar**.
Deduplication:** Uses a "Mark as Seen" node to prevent processing the same event multiple times.
Filtering:** Filters for specific events that require a follow-up ("Only Follow Ups" node).
AI Follow-up:* An *AI Meeting Agent (using Gemini/LLM)* uses the details of the past meeting and the Calendar's *Availability** tool to find and suggest open slots for a future meeting.
Communication:* Sends a message with the suggested slots via *WhatsApp (Rapiwa)* and *Email (Gmail)**.

Key Features
Scheduled Automation:** Both event creation and follow-up scheduling run on a recurring schedule.
Data Synchronization:* Reads meeting details from and updates a *Google Sheet**.
Google Calendar Integration:** Creates events and checks calendar availability.
Multi-Channel Communication:* Sends confirmations/follow-ups via *WhatsApp (Rapiwa)* and *Email (Gmail)**.
AI-Powered Follow-up:* Uses an *AI Agent (Gemini)** to intelligently find and format available slots for the next meeting, considering the details of the past meeting (day, time, duration).
Idempotency:** The "Mark as Seen" node prevents duplicate follow-up attempts for the same event.

Requirements
n8n instance with nodes: Schedule Trigger, Google Sheets, Split In Batches, Date & Time, Code, Google Calendar, Rapiwa, Gmail, Filter, Agent (LangChain), LLM Chat (Google Gemini), Structured Output Parser (LangChain), Set, Remove Duplicates, Wait.
Google Calendar** with an available calendar for event creation and availability checks.
Google Sheets** for storing meeting details.
Rapiwa** (WhatsApp API) account credentials.
Gmail** account credentials.
Google Gemini (PaLM) API** credentials for the AI agent.

How to Use — Step-by-Step Setup
Credentials Setup
Google Sheets OAuth2: Configure to allow the workflow to read from and write to your Sheet.
Google Calendar OAuth2: Configure to allow event creation and availability checks.
Rapiwa API: Set up credentials for sending WhatsApp messages.
Gmail OAuth2: Set up credentials for sending email confirmations/follow-ups.
Google Gemini(PaLM) API: Set up credentials for the AI agent functionality.

Configure "Create Event" Branch
Get in sheet: Update the Document ID and Sheet Name to point to your meeting data spreadsheet. The node is set to filter by a status column.
Create an event: Verify the correct Calendar ID is selected. The end time is dynamically generated by the previous Code node.
Rapiwa / Send a message1: Update the recipient number/email address and customize the message templates.
Update status in sheet: Ensure the correct Document ID, Sheet Name, and matching column (row\_number) are configured to update the status to "sent".

Configure "Reminder Event" Branch
Get Past Events: Verify the correct Calendar ID is selected.
Only Follow Ups: Customize the filter condition if only a subset of past meetings needs follow-up (e.g., if you have a "Follow-up Status" column to check).
Meeting Agent: Review the System Message to ensure the AI's logic for finding slots matches your business rules (e.g., preferred working hours, look-ahead period).
Generate Message: Customize the message template, which formats the AI-suggested slots.
Rapiwa1 / Send a message: Update the recipient number/email address for the follow-up messages.

Google Sheet Required Columns
The workflow expects a Google Sheet with meeting data to have at least the following columns:
A Google Sheet formatted like this ➤ Sample Sheet

| title | description | location | color_number | start time | end time | reminder status | status |
| :-------------------------------------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | :---------------- | :----------- | :----------------- | :----------------- | :-------------- | :------ |
| 2025 Personal Planner & Events Calendar | Stay organized and never miss an important date! This calendar helps........ | Dhaka, Bangladesh | 4 | 10/28/2025 3:50:00 | 10/29/2025 5:30:00 | sent | checked |
| 2026 Personal Planner & Events Calendar | Stay organized and never miss an important date! This calendar helps........ | Dhaka, Bangladesh | 2 | 10/29/2025 3:50:00 | 10/30/2025 5:30:00 | sent | checked |

Useful Links
Dashboard:** https://app.rapiwa.com
Official Website:** https://rapiwa.com
Documentation:** https://docs.rapiwa.com

Support & Help
WhatsApp**: Chat on WhatsApp
Discord**: SpaGreen Community
Facebook Group**: SpaGreen Support
Website**: https://spagreen.net
Developer Portfolio**: Codecanyon SpaGreen