Gmail Support Reply Automation: Gemini + Slack Approval (n8n)

Draft Gmail support replies with Gemini—and get Slack approval before anything goes out

This n8n workflow automatically monitors your Gmail inbox for unread emails labeled “support”, uses Google Gemini to draft a concise reply, and sends it to Slack for human approval. Approved responses are then sent via Gmail and logged in Google Sheets; discarded drafts are also recorded for full accountability.

What this workflow does

• Polls Gmail every minute for unread messages matching label:support.
• Extracts the sender, subject, and body from each email and sends that context to Google Gemini to generate:
  • a one-line summary
  • a suggested support reply
• Formats the draft with the original email metadata (recipient, subject, and thread/message IDs) and applies a fallback reply if needed.
• Posts the proposed reply to Slack in your chosen channel (e.g., #support-approvals) with “Send it” and “Discard” buttons, then waits for the approver’s decision.
• If approved, sends the reply from Gmail with the subject prefixed by “Re:”, and appends a record to Google Sheets in the Replies tab.
• If declined, does not email the customer—only logs a “discarded” outcome to the same Replies tab.

Use cases

• Reduce response time for SaaS support while keeping a human in the loop.
• Standardize support tone by generating drafts from Gmail content with Gemini.
• Create an audit trail for approved vs. discarded AI-assisted replies using Google Sheets logging.

Technical details

• n8n trigger/node flow: Gmail trigger (polling), plus if and code nodes for logic and formatting.
• Integrations: Gmail, Google Gemini (PaLM) API, Slack (OAuth2 approvals), and Google Sheets (OAuth2) logging.
• Setup requirements: Label incoming support emails in Gmail with support, ensure they are unread, and create a Google Sheets document with a Replies tab.