Conference autoinvite in freepbx

i have found several discussions on this topic but none of those were much help.
Is it possible to achieve with freepbx a conference call that will autoinvite others?
For example: I will have a number 10 creating the conference. He will dial a conference room number. Then what i want to achieve is to autodial numbers 20 and 30 and join them (10,20,30) to a conference.

Is it possible?

Thank you very much for every hint or help


That sounds like an AGI solution would be effective with “call.files”.