Gmail Wholesale Order Validator w/ GPT-4o & Google Sheets (n8n)

Automatically validate wholesale orders from Gmail using GPT-4o and your Google Sheets price list

This n8n workflow watches your inbox for new wholesale order emails, uses OpenAI (gpt-4o-mini / GPT-4o) to extract the order details, validates every line against a Google Sheets PriceList, and then sends either an order confirmation or a revision request—while logging everything and alerting your order desk via Telegram.

What this workflow does

• Monitors Gmail every minute for unread messages matching the filter: is:unread subject:(wholesale order).
• Normalizes key email fields (sender, subject, received time, and body text). Very short emails are routed to an error log.
• Extracts structured order data with OpenAI (customer details, PO number, delivery date, notes, and line items) from the email body.
• Validates lines against Google Sheets by loading the PriceList tab and checking: valid SKUs, active status, case-pack multiples, and any quoted price mismatches.
• If problems are found, it emails a revision request to the customer listing the issues, logs the order to the Orders tab, and alerts the order desk via Telegram.
• If no issues are found, it emails an order confirmation (with priced lines), logs the order, and alerts via Telegram.
• Marks the original Gmail message as read after the order is logged.
• Weekly digest: Every Monday at 08:00, it reads the past week’s Orders, uses OpenAI to generate a short digest email, sends it via Gmail, and posts a Telegram summary.

Use cases

• Automate wholesale order intake and reduce manual SKU/price checking.
• Catch quoting and packaging issues early by validating case-pack multiples and price mismatches.
• Keep operations informed with Telegram alerts plus a Monday digest.

Technical details

• n8n workflow with nodes including: if, set, code, gmail, telegram, and sticky note.
• Uses OpenAI (gpt-4o-mini) for order extraction and digest generation.
• Reads and writes Google Sheets tabs: PriceList and Orders.