Automate Sales Follow-Up with Google Calendar and AI Agents in n8n

What this workflow does

This workflow helps you never forget to follow up after sales meetings. It finds meetings from 2 to 4 days ago in your Google Calendar. If there is no follow-up email, it flags the meeting. It suggests new meeting times and lets you choose if you want to book a next call. You save time and lower chances of missing opportunities.

Who should use this workflow

• People who have lots of sales or client meetings.
• Users who want to save time and avoid missing follow-ups.
• If you forget to send emails or book next calls after meetings.

Tools and services used

• Google Calendar: Finds your meeting times.
• Gmail: Checks your emails after your meetings and sends approval message.
• OpenAI GPT (through LangChain): Suggests meeting times and reads your reply.
• n8n: Runs all steps and connects your accounts.

Inputs → Process → Output

Inputs

• Your sales Google Calendar.
• Your Gmail account.
• Your OpenAI API Key.

Processing Steps

1. Schedule Trigger: Runs every day at 6 AM.
2. Google Calendar (Get Past Events): Finds events from 2-4 days ago.
3. Remove Duplicates: Removes events already handled.
4. Split In Batches: Checks meetings one by one.
5. Gmail (Get Emails Since): Looks for emails with attendees after the meeting.
6. Set: Flags meetings with no follow-up emails.
7. Filter: Keeps only those needing follow-up.
8. LangChain Agent (Meeting Availability Agent): Suggests new times for next meeting.
9. Output Parser Structured: Makes suggestions easy to read.
10. Set: Makes approval message for you.
11. Gmail (Send for Human Approval): Emails you with choices, waits for your reply.
12. LangChain Agent (Meeting Booking Agent): Reads your reply and books the meeting if you agree.

Output

• You get a clear summary email every day about which leads need action.
• If you approve, the next meeting gets booked automatically for you.

Beginner step-by-step: How to build this in n8n

Import and setup

1. Download the workflow using the Download button on this page.
2. In the n8n editor, click Import from File and select the file you downloaded.
3. Wait for the workflow to load.

Connect your accounts

1. Add your Google Calendar API Key where the Google Calendar nodes say ‘credentials’.
2. Add your Gmail API Key for all Gmail nodes.
3. Paste your OpenAI API Key in the right field for the LangChain Agent nodes.

Update fields

1. Type your sales calendar’s ID (see Google Calendar settings) in the Google Calendar nodes.
2. Double-check email addresses set in Gmail nodes so it sends and checks the right inbox.

Check and test

1. Look at each node for red error marks — fix if needed.
2. Click Test Workflow for a test run. You should receive an approval email if there’s a meeting in the window with no follow-up.

Go live

1. Click Activate at top right in n8n.
2. The workflow is now in production.

For self-hosting n8n

You can use self-host n8n if you run your own server or VPS.

Customization ideas

• Change date range: Edit the Google Calendar node to check more or less days.
• Change message: Update the message text in the node where suggestions are sent.
• Add Slack or Telegram: Swap the email step for chat if preferred.
• Switch to Office 365: Use Outlook Calendar/Gmail nodes if your company uses Microsoft accounts.

Edge cases and problems

• No emails found: Check the email addresses in your Gmail node are correct.
• No slots found: Check Google Calendar access; open time range wider in the agent prompt if needed.
• Email approval not working: Make sure the Gmail send-and-wait setup uses your real email address.
• Empty event list: May mean no meetings in the time window — try changing Google Calendar search dates.

Results summary

• ✓ Workflow stops you from missing follow-ups.
• ✓ You get choices for next meetings in your email every day.
• ✓ One reply can book a meeting automatically for you.
• → Less stress, more closed deals. Faster sales. Less time wasted.