n8n Gmail Auto-Reply Drafts with OpenRouter Qwen + Docs RAG

Auto-Reply Gmail emails with Qwen—when it’s safe, draft for review when it isn’t

This n8n workflow watches your Gmail inbox, uses OpenRouter (Qwen) to decide whether an incoming message should be auto-replied, drafted for human review, or ignored—and grounds its responses using your Google Docs knowledge base.

What this workflow does

• Checks for new Gmail messages every minute using a Gmail trigger.
• Fetches the full email content (via the Gmail message ID).
• Classifies the email with OpenRouter (Qwen) as one of three actions: Reply, Draft, or Nothing—based on sensitivity and whether action is required.
• If classified as “Reply”: retrieves relevant reference content from a Google Docs knowledge base, generates a final response with Qwen, and sends the reply in Gmail.
• If classified as “Draft”: pulls reference content from the same Google Docs sources, generates a suggested response with Qwen, and saves it as a Gmail draft threaded with the original conversation and addressed to the sender.
• If classified as “Nothing”: the workflow takes no further action.

Use cases

• Reduce support response time by auto-replying common, low-risk questions while sending higher-sensitivity emails to draft mode.
• Turn internal documentation into actionable email responses by grounding answers in your Google Docs knowledge base.
• Give teams a “human review” safety net: sensitive messages become Gmail drafts instead of immediate sends.

Technical details (n8n + integrations)

• Gmail Trigger (polls every minute) + Gmail actions for reading, replying, and creating drafts.
• OpenRouter API using Qwen (example model: qwen/qwen-2.5-7b-instruct).
• Google Docs Tool to pull reference content from two knowledge-base document URLs.
• Workflow control via nodes including Switch (Reply/Draft/Nothing branching), plus supporting nodes like NoOp and Sticky Note.

Setup requirements: connect OAuth2 credentials for Gmail and Google Docs (read, reply, create drafts; and Docs access), add an OpenRouter API credential, and replace the two Google Docs document URLs with your own knowledge-base files.