Are there any guidelines for the Apple Pencil yet?

None are available yet. I've done a fair amount of searching myself to determine the answer to one

very nagging question, how can the Pencil be used if one rests their hand on the screen and most

artists do when using paper and pen/pencil.

Apple purchased fingerworks, which supported touch radius. Recenty, appled opend up some of the API with [touch majorRadius], with three levels. Am sure there are more levels, internally. As long as your hands/fingers are wider than the tip of the pencil. Should be ok. Maybe a problem for your dog to use it though - claws and all.

I am very curious about stylus tilt. Does it work like the Wacom/Wintab driver which has tilt x y? Or is it simply one measurement. Have used X Y to determine direction of stylus. Somewhat like a virtual joystick. Extremely important for 3D fly-throughs.

Are there ways to start using pen strokes in my app now, assuming I am targetting 9.1 and iPad Pro?