Are lore rolls to detect magic automatic?

Question

I know from reading the volume 1 rule book, that the presence of magic such as with trap-wards and ghosts (examples used as they are cited in the book), can be detected by a magic user rolling well on lore - however, I'm not sure on if the roll is supposed to be automatic or not? According to the rules of the system.

As in, if there is something like a magical trap set or a non-visible ghost present: by the rules, is the GM be supposed to automatically call for magic-users to roll lore to detect magic, or do the players have to decide themselves if they want to make a roll to check an area?

I've perhaps missed something somewhere in the book clarifying this.

Answer 1

Lore-as-magic-sense is something the GM will generally prompt you to roll.

Trapping: Mystic Perception

Exposure to arcane lore leads to a heightened sense of the supernatural. In certain circumstances, you can substitute Lore for Alertness to pick up on supernatural details about a scene. These details should be extremely vague, limited to statements such as "You're getting a bad feeling about this" or "Something about this place is just... wrong." Used this way, Lore is more an indicator that there's something weird happening rather than a lens through which to see the weird.

• Dresden Files: Your Story p.135, "Lore"

So, how does Alertness work?

Trapping: Passive Awareness

You will rarely ask to roll Alertness - if you are actively looking for something, Investigation is usually more appropriate. Alertness is reactive perception. That is, Alertness is more appropriate for things that you do not expect or are not looking for - such as the spiked pit trap in the hallway you're casually walking through. It's a skill that, typically, the GM calls for you to roll.

• Dresden Files: Your Story p.121, "Alertness"

Sticking the two together produces this conclusion: if there's magic about that the GM wants you to be aware of, they'll ask you to make a Lore roll to find it. But at a baseline you'll need to do some additional research or investigation to pick up on exactly what's going on, though a large margin of success on the Lore roll might obviate some of that.