I like the game, cause I don't believe I've seen a stealth game yet. But it was a little too confusing; I didn't even know it was a stealth game at first and couldn't figure out why I was dying. I was completely guessing whether I'd die or not as there is no real indicator to show where I can and can't go. As others said, maybe show us the line of sight.
As a whole, not bad but certainly room for improvement.