Setup guide · about 10 min

Gmail AI Reply Drafts: setup guide

Every 5 minutes it checks for new unread emails from real people. Skip Seen + Newsletters drafts each email only once and ignores automated mail. The AI answers only from the business info you give it, never invents prices or promises, and keeps replies under 140 words. Nothing is sent until you press Send.

How it works

Both groups expanded: Gmail trigger, Prepare (settings + filters), Draft the reply (AI + Gmail draft).

A real test: the customer asks about Saturday hours and price; the draft answers from the business info, with the booking link.

STEP 01

Import the workflow

In n8n open Overview → Create Workflow, then the ⋯ menu (top right) → Import from File and pick the .json file. Sticky notes on the canvas repeat the key steps.

STEP 02

Connect Gmail

Open New Email → Credential → Create new → Sign in with Google. Use the same credential in Save Gmail Draft.

Self-hosted n8n? Google sign-in needs your own OAuth app: in Google Cloud Console create a project, enable the API (Gmail and/or Sheets + Drive), set up the consent screen with yourself as a test user, and create a Web application OAuth client with redirect URI https://YOUR-N8N-URL/rest/oauth2-credential/callback. Paste the Client ID and Secret into the n8n credential.

STEP 03

Connect the AI

Open AI Model and create an OpenAI credential:

	Gemini (free tier)	OpenAI
API key	aistudio.google.com/apikey	platform.openai.com
Base URL	`https://generativelanguage.googleapis.com/v1beta/openai`	default
Model (By ID)	`gemini-3.5-flash-lite`	`gpt-5-mini`

For Gemini keep Use Responses API off. Older names like gemini-2.5-flash return a 404 for new keys.

STEP 04

Tell the AI about your business

Open Prepare → Settings. The AI uses only what you write here: yourName, business (what you sell, prices, hours, links, policies), tone and signature.

The only place you type your business details.

STEP 05

Optional: narrow the inbox search

The search in New Email is in:inbox -category:promotions -category:social -category:updates -from:me. Add any Gmail search, e.g. to:hello@yourdomain.com.

STEP 06

Publish

Click Publish. Send yourself an email from another account to try it.

Troubleshooting

No draft appears

The email must be unread, in the inbox, and not from your own address. No-reply senders and newsletters are skipped on purpose.

AI Model error: 404 / model not found

Check the model ID and Base URL above; use a model your key can access, e.g. gemini-3.5-flash-lite.

Replies are too vague

Add more detail to business in Settings: prices, hours, links, and what you don't offer.

Google sign-in stops working after 7 days

Your OAuth app is in Testing mode. In Google Cloud → OAuth consent screen, click Publish app.

Need help?

Email hello@workflowvault.shop with a screenshot of the node and the error. Want it installed for you? Ask for a Template install.

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