And then Phix asks:
"So, what could be done to portals to make them less vulnerable to small invisible monster spies?"
"Technically," offers Prime, "We can also put magical markers on the chips - that's bad for large-scale, because of the mana and mage requirement, but that might be good for your set of planes just so you can go there yourself."
"That'd be very nice, yes. Prevent invading demons and angels. And fairies, for that matter."
"If we make them easily-scryable, that doesn't just apply to Prime and I, that's all mages. So if they know we have them, and know what to look for, they can easily find us."
"Get Ice to ward them? I don't know if she can do that if I materialize them inside people's abdominal cavities though. Or if she can make it selective as to who it hedges out."
Wedding rings! Useful things, his especially. He can just call his wife where she is at home.
"Love, do you have a minute?"
"Yes, but just barely, the accountant'll show up for the appointment any minute, what is it, love?"
"We are thinking of putting easily-scryable microchips in us that would also work as keys to portals. The problem, there, is that if mages found out they could easily scry for any of us. Do you have a witchy solution?"
"Consulting alethiometer... Wards not discriminate watcher. That sounds like a no, no best of both worlds. Sorry."
"How likely are you guys to need to be able to scry on us when you can't find us just from having met us?"
"I think being findable to help is more important than being slightly harder to find for people who probably won't even know how to find us in the first place."
"I'm inclined to agree, especially if we make whatever it is obscure and really specific. We can have certain locations warded, if that helps?"
Cam makes a whiteboard attached to an empty area of wall. "We can make Ice a to-do list."
These items appear on the whiteboard. "And I can microchip everybody once we have a design and the portals can be modified to make it worthwhile."