awareness & Contingency triggers

[threemilechild]

My sorceress has been killed/mauled by black dragons several times, and having just gotten access to Contingency, cast a Mirror Image contingent on being within 100' of a black dragon.

Contingency states that the triggered spell occurs whether I want it to or not, so I assumed my knowledge was irrelevant. My DM is unsure. What do you all think?

Contingency excerpt wrote:

The conditions needed to bring the spell into effect must be clear, although they can be general. In all cases, the contingency immediately brings into effect the companion spell, the latter being “cast” instantaneously when the prescribed circumstances occur. If complicated or convoluted conditions are prescribed, the whole spell combination (contingency and the companion magic) may fail when triggered. The companion spell occurs based solely on the stated conditions, regardless of whether you want it to.

[Rogue Eidolon]

It should be something you could reasonably perceive or know, whether you want it or not. Unfortunately, that leads to a lot of possible table variation. But if you allow contingency on something you can't perceive or know, you could use it to answer questions in a bizarre way (for instance, contingency to cast mirror image if P=NP)

[sunbeam]

This is a knotty spell. Always has been. I've seen it run a whole lot of ways.

In the end this thing is just not defined enough to do anything else but house rule it. And it's been that way since 1e (hmmm can't remember if this was Unearthed Arcana, or it was in the PH. I'm not digging it up.)

Okay how does Contingency "know" things. What senses does it have. Can it identify spells being cast?

I've seen it used for things like this: "If someone tries to cast dimensional anchor on me, my contingency will teleport me away before that happens." How does contingency know a spell is being cast, let alone which one?

Or: "If I am about to be attacked, contingency will cast Greater Invisibility on me."

Does contingency know things you don't? Like you are about to be attacked?

This spell sounds cool, but there is a lot of devil in it's details.