ToBufferDescription (get elements from inner array) in VL

open the document patch and add a Record there and give it a name, or press Ctrl+P to make a new patch and set it to Record and give it a name both actions are the same.

the add pads to it, name it like stuff you want to store (Positions, Normals etc.) and add inputs and outputs for it and assign the inputs to Create and the outputs to new operations like GetPositions, Split etc.