Jeff Rients has some great advice on the topic of making PC actions explicit:

Don’t make the enigmatic figure behind the screen guess what you are trying to accomplish. Sometimes the GM is mentally juggling more stuff than is immediately obvious. Do yourself a favor and connect the dots for whoever is wearing the viking hat.

That’s something that’s well worth bringing up with your group, and it’s an easy way for your players to give you a hand with the often complex art of running the game.

As a GM, I don’t mind when players “spoil” this kind of surprise — for me, the surprise comes when they describe the idea, or it works really well, and not from being in the dark.