Smart Gmail auto-labeler with Gemini AI & sender history

n8n Gmail AI Auto-Labeler > An intelligent n8n workflow that automatically classifies and labels Gmail emails using Google Gemini AI, keeping your inbox organized with zero manual effort. This workflow uses AI-powered classification to analyze email content, learn from sender patterns, and automatically apply appropriate labels while archiving processed emails. --- How It Works 1. Trigger: The workflow runs automatically every minute to check for new unread emails (or manually for bulk processing). 2. Check for Existing Labels: Before processing, it verifies if the email already has an AI-assigned label to avoid duplicate processing. 3. AI Classification: If unlabeled, the AI agent analyzes the email using: Sender History Tool - Fetches up to 10 previous emails from the same sender to identify patterns 80% Majority Rule - If 80%+ of sender's past emails have the same label, strongly prefers that category Label Examples Tool - When uncertain, compares the email with existing examples from suspected categories 4. Smart Decision: The AI returns a structured JSON response: json { "label": "Category Name" } Or "None" if no category fits. 5. Apply & Archive: Label Applied → The workflow adds the appropriate Gmail label to the thread. Auto-Archive → Removes the email from INBOX (archives it) to maintain zero-inbox. 6. Loop: Processes the next email in the batch, ensuring all new emails are classified. --- Requirements Gmail OAuth2 Credentials - Connected Gmail account with API access. Google Gemini API Key - Get it here Free tier: 15 requests/minute Gmail Labels - Must be created in Gmail exactly as listed: Meetings Income Inquiries Notify / Verify Expenses Orders / Deliveries Trash Likely --- How to Use 1. Import the Workflow: Copy the provided JSON file. In your n8n instance → click Import Workflow → select the JSON file. 2. Create Gmail Labels: Open Gmail → Settings → Labels → Create new labels. Use the exact names listed above (case-sensitive). 3. Get Your Label IDs: In the workflow, click "When clicking 'Execute workflow'" manual trigger. Execute the "Get Labels Info" node only. Copy each label's ID (format: Label1234567890123456789). 4. Update Code Nodes with Your Label IDs: Node 1: "Check Label Existence" javascript const labelMap = { "LabelYOURIDHERE": "Meetings", "LabelYOURIDHERE": "Inquiries", "LabelYOURIDHERE": "Notify / Verify", "LabelYOURIDHERE": "Expenses", "LabelYOURIDHERE": "Orders / Deliveries", "LabelYOURIDHERE": "Trash Likely" }; Node 2: "Convert Label to Label ID" javascript const labelToId = { "Meetings": "LabelYOURIDHERE", "Inquiries": "LabelYOURIDHERE", "Notify / Verify": "LabelYOURIDHERE", "Expenses": "LabelYOURIDHERE", "Orders / Deliveries": "LabelYOURIDHERE", "Trash Likely": "LabelYOURIDHERE" }; 5. Set Up Credentials: Gmail OAuth2 → Authorize your Gmail account in n8n. Google Gemini API → Add your API key in n8n credentials. 6. Test the Workflow: Send yourself test emails with clear content (e.g., invoice, meeting invite). Use the manual trigger to process them. Verify labels are applied correctly. 7. Activate for Auto Mode: Toggle the workflow to Active. New unread emails will be processed automatically every minute. --- Notes Dual Execution Modes: Auto Mode - Gmail Trigger polls inbox every minute for unread emails (real-time processing). Manual Mode - Use the manual trigger to bulk process existing emails (adjust limit in "Get many messages" node). AI Learning from Patterns: The workflow applies an 80% majority rule - if 80% or more of a sender's historical emails share the same label, the AI strongly prefers that category for new emails from that sender. This creates intelligent sender-based routing over time. Skip Already Labeled Emails: The "Check Label Existence" node prevents re-processing emails that already have an AI-assigned label. Ensures efficient execution and avoids duplicate work. Structured AI Output: Uses a Structured Output Parser to ensure the AI always returns valid JSON: { "label":