You left it wide open. That click was the sound of the trapdoor being shut.
Clinging to the top of the cage like this, you can’t see who’s coming. But you definitely hear heavy footsteps echoing through the otherwise silent cave.
This isn’t just a piece of enchanted paper you can read to release a spell! This is a 300 page book explaining how to cast one. It would take you over an hour to read this in its entirety. You have about nineteen minutes before the invisibility cloak blinds you – and probably less than one minute before those footsteps get down to you.
Regardless, you flip through enough pages to determine that the book explains a summoning spell, not a teleportation one. All six books seem to be identical and a large amount of pages are dedicated to explaining jargon, suggesting these were probably used for a classroom of magic students.
The footsteps are getting louder. You stow the book back in your inventory before it can give you away.
Oh, right! You guess you skipped those.
Acting fast, you quietly pop the lid off one of the barrels. It’s full of water, and picking up water is apparently not within the scope of telekinesis. Without even trying, you assume the barrel is too heavy to telekinetically tip.
The other one, though… that looks like imp gall. You’ve had no problem telekinetically picking up globs of it before. If you’re quick, you could probably grab a little bit to-
I see you’ve found my lucky bowling ball! And I don’t mean that facetiously – it actually has a minor luck enchantment. It gets a strike every time.