Calendar Conflict Responder

24 Feb 2026

I’m sure that many, like me, live by their Google Calendar. My daily activities follow a schedule of classes, meetings, and other activities that I only show up for if I or someone else has put them on my calendar. When I co-teach a lesson, my co-teacher is the one who schedules the time on my calendar. Unfortunately, without realizing it, sometimes a colleague schedules something on my calendar when I already have another activity. Trying to rectify the booking can be time consuming for both of us.

This had been frustrating me for years. I can’t do appointment slots, as we have a rotating schedule that is quite complicated. I have been doing a lot of experimenting with having Gemini writing code for me, including a Bingo Card Creator & a Softball Call Sheet Generator. I decided to ask Gemini if there was a way to automatically email people when they schedule something at a time I already have an appointment on my calendar. And there is!! A “double-booking” automatically triggers an email to the person who booked the appointment, letting them know the time slot is not available.

After some trial and error, Gemini came up with the script that you can find here (partial screenshot below). Open Apps Script to get started. Paste the code into a New Project. Save & Run and give the script the permissions it asks for. It works perfectly. Feel free to use it or adapt it as you wish.