[@Keksalot]
-A faerie can say something that is not true if they think it is (i.e. they are wrong).
-A faerie can imply something that is not true, if they do not directly say it.
-Faeries do not have to correct someone if they say something wrong, and they often do so to mislead people.

-In the first example, if he was not aware that the object was green, saying it was red instead would be fine. Whether gestures can count as lying I don't know, though I expect that something as obvious as pointing would. They could say "There is something red near me", if, for example, they wore a red ring.
-In the second example, the meaning of the statement (to the assassin) is that X should be killed. The faerie could say they did not order X's death only if they were saying these were not their exact words.
-In the third example, the first answer would probably not be acceptable, but I think the other two would.

Ultimately there is no rule that will work every time. If you're not sure, ask me, BC or Nallore in a PM before you post. There is the possibility that one of us will ask you to edit a post if we think you have directly lied, but for the most part you should be fine.