I've laid squares of chicken wire over recently-sown beds. I don't think cats like the way it feels on their feet, or they get tangled. I try to prop it up on the surrounding raised bed walls to keep seedlings from getting tangled. The bricks were intended to keep squirels out, but I think it only works if they have plenty of other things to eat.
The holes are hexagons around 1" across, so maybe that would be too small to catch snakes?
I also tried laying down a criss-cross of thin bamboo culms and thorny twigs, but they were just decorations on the catbox:
