n8n Lead Response Automation: OpenAI, Gmail & Google Sheets

Automate every lead reply: OpenAI spam screening + Gmail (send or draft) + Google Sheets logging

This n8n workflow captures new enquiries from an n8n Form or a website webhook, uses OpenAI to detect spam and generate a short, safe reply, then sends (or drafts) it via Gmail. It also alerts you and logs every lead and outcome to Google Sheets—so nothing slips through.

What this workflow does

• Receives new enquiries from an n8n Form submission or a POST request to a webhook endpoint.
• Normalizes lead data (name, email, phone, service, message) into a single lead record and timestamps when it was received.
• Uses OpenAI for spam screening by labeling the message as real or spam.
• Routes outcomes safely: auto-reply for real enquiries, “log-only” for non-reply scenarios, or “needs a person” when the check fails or the email is invalid.
• Prevents duplicate responses by checking your Google Sheets log to see if the same email already received a reply within a configured time window.
• Generates a short reply for new real enquiries, including your booking link, and applies safety checks (risky content is replaced with a fixed fallback reply).
• Sends or drafts via Gmail based on the DRAFT_ONLY setting.
• Notifies the owner by email (optionally via Twilio SMS and Telegram if enabled), and appends the lead + outcome to Google Sheets including seconds-to-reply.

Use cases

• Your website generates inquiries and you want instant responses without manual copy/paste.
• You receive high volumes of spam and need OpenAI-based filtering before contacting leads.
• You want measurable lead handling—every enquiry logged with outcome and response time in Google Sheets.

Technical details

• OpenAI via HTTP Request using an Authorization header (Bearer API key) for spam labeling and reply drafting.
• Gmail to create drafts or send emails depending on DRAFT_ONLY.
• Google Sheets to detect repeat emails and record lead/outcome/seconds-to-reply.
• Workflow logic uses if, set, code, switch (and includes twilio for SMS alerting).