I solved it.
If you want to schedule a surprise party for John Doe you have to say this exactly: "schedule quote surprise party for John Doe end quote at 1pm tomorrow."
Example if you say: "Schedule quote surprise birthday party for John Doe. end quote for November 8th at 9pm" then Siri will NOT send a meeting invite to John Doe for the surprise party.
Example if you say: "Add quote appointment with Dr. Nick end quote on Nov..." will NOTsend an e-mail notification to Dr. Nick...
I want to tell Siri to "schedule lunch with Joe at noon" so it ends up on my calendar, but so it doesn't email Joe as an invitee. Is this possible?
Schedule quote lunch with joe end quote at noon No email will be sent