Vapi Voice Receptionist Booking w/ n8n Google Calendar & Sheets

Turn Vapi phone calls into real Google Calendar bookings—automatically

This n8n workflow connects a Vapi Voice Receptionist to your Google Calendar and Google Sheets. It handles availability checks, books appointments, captures phone messages, logs every outcome, and emails you the details—all triggered by Vapi tool calls via a production webhook.

What this workflow does

• Receives Vapi webhook events via POST and extracts the tool name, tool call ID, and arguments from the payload.
• Routes requests by tool name using a switch-style flow so each action (availability, booking, or message capture) is handled correctly.
• checkAvailability: fetches upcoming events from Google Calendar, then computes the next available appointment slots using configurable business-hour rules.
• Returns slot options to Vapi in a spoken-ready response that includes ISO timestamps for booking.
• bookAppointment: creates a new Google Calendar event at the requested startTime, appends a booking record to Google Sheets, and emails the owner a booking alert.
• takeMessage: appends the caller’s message to Google Sheets, emails the owner the message details, and sends a confirmation back to Vapi.
• Non-tool-call events: returns an empty acknowledgement to Vapi without taking action.

Use cases

• A SaaS or services business using Vapi to answer calls can offer real-time scheduling and capture missed-call messages.
• Operators can centralize appointment + message logging in Google Sheets while receiving email alerts for every booking or voicemail.
• Automation engineers can deploy a production-ready Vapi-to-calendar routing pattern for voice-driven scheduling workflows.

Technical details

• Integrations: Vapi (webhook), Google Calendar, Google Sheets, email notifications.
• n8n nodes/approach: Webhook, Code, Switch, Google Calendar, Google Sheets, Email Send, plus a Sticky Note for documentation.
• Vapi setup: create server tools for checkAvailability, bookAppointment, and takeMessage pointing to the workflow’s production webhook URL.