I setup my first n8n automation using a Vapi voice assistant to set google calendar appointments. I first set it up using the built in Vapi google calendar tool for checkAvailability and createEvent. It worked well for checking availability and creating events, but when a caller tried to reschedule an event, it could only create a new event (leaving the old one still on the calendar which is a problem). I then switched my n8n workflow to use an MCP trigger. I created an mcp_tool in Vapi and used that instead in my system prompt and that also worked for creating events but it cannot recall the eventID so my Update calendar branch never runs and the reschedule fails. I’m assuming this is a common problem and was wondering how to correctly capture the data so I can use my Vapi assistant to not just create events but also lookup to reschedule or cancel events. I do have webhook which sends the appointment details to a google sheet, i can also have it send the eventID there, but i’m not sure how to have the MCP trigger call it and send it back to Vapi for rescheduling. I’m open to other ways of doing this if there’s an easier/better method. Thanks for your help!
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