This extension adds a customizeable description to every Google Calendar Invite you createIf you've ever had to copy paste your Dial-in information, or a conferencing application link into a meeting event every time you set one up, you know what problem this solves. Google Calendar doesn't let you set up template events or default signatures for Event descriptions, so you have to put it in every time. This lets you create a default signature for all new events.
Notes: Doesn't work for quick add, won't work on mobile or your apps
Reviews of GCal Event Default Description extension