Stop losing time on back and forth emails. This setup scans new Gmail messages and sends a clear meeting reply using your Google Calendar availability. It fits teams that get appointment requests by email and want fast, helpful answers.

Here is how it works. Unread Gmail messages are checked every minute. An AI model reads the subject and body and labels if it is an appointment request. If it is, an agent pulls the next month of Google Calendar events, keeps only confirmed items with set times, extracts start and end, sorts them, and formats availability as a simple list. The agent then writes a friendly reply that offers times and sends it through Gmail, and the email is marked as read.

Setup needs Gmail, Google Calendar, and an OpenAI API key in n8n Cloud. Pick your calendar, confirm permissions, and keep the default workflow link unless you split the availability into a second workflow. Expect faster replies, fewer double bookings, and a smoother inbox. This is great for sales outreach, client onboarding, and service bookings where email is the main channel.

• Gmail Trigger polls unread messages every minute and ignores spam and trash.
• Chat OpenAI model with low temperature classifies if the email asks for a meeting.
• Structured Output Parser returns a clear is_appointment field for routing.
• Google Calendar node reads events for the next month with single events enabled.
• Filter keeps only confirmed events with a start time, then extracts start, end and title.
• Sort orders times, Item Lists and Set nodes build a clean availability response.
• An Agent uses a Workflow Tool to fetch availability as JSON, drafts a friendly reply, sends it via Gmail, and marks the thread as read.

• Cut reply time from 10 minutes to under 1 minute
• Automate up to 90 percent of appointment emails
• Reduce double booking by checking confirmed events
• Handle five times more scheduling requests without extra staff
• Connect Gmail, Google Calendar and OpenAI in one flow
• Improve response speed to minutes, not hours

1. Import the template into n8n: Create a new workflow in n8n > Click the three dots menu > Select 'Import from File' > Choose the downloaded JSON file.
2. You'll need accounts with Gmail, Google Calendar and OpenAI. See the Tools Required section above for links to create accounts with these services.
3. Open the Gmail Trigger node and create a new Gmail OAuth2 credential. In the credential dropdown, click Create new credential and follow the on screen steps to grant access to your Gmail account.
4. Open the Send Reply and Mark as read Gmail nodes and select the same Gmail credential to allow sending and updating messages.
5. Open the Google Calendar node and create a Google Calendar OAuth2 credential. Pick the calendar you want to use for availability.
6. Open both Chat OpenAI nodes and create an OpenAI API Key credential. Paste your API key from your OpenAI account and select the gpt 4 model with the given temperature.
7. Confirm Gmail Trigger settings: unread filter is on and polling is every minute. Adjust frequency if needed.
8. Check the Execute Workflow Trigger and Workflow Tool nodes. If you keep everything in one workflow, leave the workflowId set to the current workflow id. If you split availability into a second workflow, update the id to match that workflow.
9. Verify the Google Calendar node options: timeMin is now minus one day, timeMax is plus one month, single events is true, and return all is true.
10. Enable the workflow and run a test by sending an email that asks for a meeting. Watch the execution in n8n to see the classifier, calendar fetch, and reply.
11. If no reply is sent, check Gmail permissions for send access, confirm your OpenAI key is active, and make sure the Calendar node is linked to the correct calendar.
12. If times look wrong, check your n8n timezone and ensure calendar events have dateTime fields and are confirmed. Review the Filter and Extract nodes for correct fields.