Smart Email Auto-Responder with AI Classification

Automatically Categorize and Reply to Emails using LangChain + Google Gemini + Gmail + SMTP + Brevo

This n8n workflow is designed to intelligently manage incoming emails and automatically send personalized responses based on the content. It classifies emails using LangChain's Text Classifier, sends HTML responses depending on the category, and updates Gmail and Brevo CRM accordingly.

Key Features

Triggers and Classifies Emails

• Listens for new Gmail messages every hour
• Uses AI-based classification to identify the type of inquiry For Example:
  • Guest Post
  • YouTube Review
  • Udemy Course Inquiry

Responds Automatically

• Sends professional HTML replies customized for each type
• Uses SMTP to deliver emails from your domain

Enhances Workflow with Automation

• Marks processed emails as read
• Applies Gmail labels
• Adds sender to Brevo contact list

Optional AI Chat Integration

• Uses Google Gemini (PaLM 2) to enhance classification or summarization

Tools & Integrations Required

1. Gmail account (OAuth2)
2. LangChain (Text Classifier node)
3. Google Gemini API account
4. SMTP credentials (e.g., Gmail SMTP, Brevo, etc.)
5. Brevo/Sendinblue account and API key

Step-by-Step Node Guide

1. Gmail Trigger

Polls Gmail every hour for new emails.
Filters out internal addresses (e.g., @syncbricks.com).
Avoids replying to already-responded emails (Re: subject filter).

2. LangChain Text Classifier

Uses AI to categorize the content of the email based on pre-defined categories:

• Guest Post
• Youtube
• Udemy Courses

3. Google Gemini (PaLM) Chat Model (Optional)

Provides additional AI support to enhance classification accuracy.
Can be used to summarize or enrich the context if needed.

4. Email Send Nodes

Each response category has a separate SMTP node with a custom HTML email:

• Guest Post Inquiry
• YouTube Video Inquiry
• Udemy Course Inquiry

5. Gmail: Mark as Read

Marks the email so it isn’t processed again.

6. Gmail: Apply Label

Adds a label (e.g., Handled by Bot) for organization.

7. Brevo: Create/Update Contact

Saves the sender to your CRM for future communication or marketing.

Email Templates Included

Guest Post Template

Includes pricing, website list, submission guidelines, and payment instructions.

YouTube Review Template

Includes package pricing, review samples, video thumbnails, and inquiry instructions.

Step by Step Tutorial

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N8N COURSE

n8n Book

More courses:
http://lms.syncbricks.com

YouTube Channel:
https://youtube.com/@syncbricks

How to Use

1. Import the template into your n8n instance.
2. Configure your Gmail OAuth2 and SMTP credentials.
3. Set up your LangChain Text Classifier and Google Gemini API credentials.
4. Update label ID in the Gmail node and ensure all custom fields like from.value[0].name match your use case.
5. Run the workflow and watch it respond intelligently to new inquiries.

Best Practices

• Always test with mock emails first.
• Keep the Google Gemini node optional if you want to reduce cost/API calls.
• Use Gmail filters to auto-label certain types of emails.
• Monitor your Brevo contacts to track new leads.

Attribution & Support

Developed by Amjid Ali
This template took extensive time and effort to build. If you find it useful, please consider supporting my work.

Buy My Book:
Mastering n8n on Amazon

Full Courses & Tutorials:
http://lms.syncbricks.com

Follow Me Online:
LinkedIn: https://linkedin.com/in/amjidali
Website: https://amjidali.com
YouTube: https://youtube.com/@syncbricks