Minecraft Structure Block format

Stuff surrounded with square brackets is optional
"*" means repitition

<root> (compound)
    |--- version (int)
    |--- [author] (string)
    |--- blocks (list)
         |--- <block>*
    |--- entities (list)
         |--- <entity>*
    |--- size (list)
         |--- 3 int components

<block> (compound)
    |--- pos (list)
         | --- 3 int components
    |--- state (int)
    |--- [nbt] (compound)
         |--- tile entity data

<entity> (compound)
    |--- pos (list)
         | --- 3 double components
    |--- blockPos (list)
         | --- 3 int components
    |--- [nbt] (compound)
         |--- entity data