How to invite new participants via meet external api?

I’ve been reading and trying out different api calls in meet external api based on this:

However, I am confused with this You can invite new participants to the call with the following API function

api.invite([ {...}, {...}, {...} ]).then(() => {
    // success
}).catch(() => {
    // failure
});

NOTE: The format of the invitees in the array depends on the invite service used for the deployment.

My question is what is invite service? Are there any example or documentation about the parameters I need to pass?

Thanks a lot.

The invite service is configured using config.js and inviteServiceUrl. This is a http endpoint you will use to invite participants.
A simple example will illustrate it easier: You have a desktop app embedding iframeAPI, doing authentication and some other way of communicating between clients … if you pass in the invite [ {id: 123}, {id:234}] this is the array of json objects that will be send to your configured invite service, the invite service will use this other way of notifying your clients and will show them some UI that they are invited to a meeting sending them URL to join.