{
    // More info on template pools can be found here: https://minecraft.gamepedia.com/Custom_world_generation#JSON_format_8
    // Yes, worldgen json files can have comments. Minecraft does "lenient" parsing of these json files.

    // This is the name of the template pool itself. I tend to just put the file path and file name here with modid.
  "name": "mvs:medium_bamboo_cart/start_pool",

    // The template pool to refer to if the entries in 'elements' fails to generate.
  "fallback": "minecraft:empty",

    // Here you can list as many nbt files or placed features to spawn.
    // Do note that placed features needs a special element entry stuff.
  "elements": [
    {

        // How likely out of all the element for this one to be chosen.
      "weight": 1,
      "element": {

          // The Identifier of the nbt file itself of the structure piece.
          // Note, this will automatically check into the 'structures' folder for the nbt file.
          // The final path would look like 'resources/data/structure_tutorial/structures/run_down_house_left_side.nbt'
          // The Jigsaw block in the structure will point to side_pool.json to spawn the other half of the house.
        "location": "mvs:carts/medium_bamboo_cart",

          // Processor JSON files can be used to randomize or replace blocks dynamically. Here, we don't do any of that.
        "processors": "minecraft:empty",

          // If set to 'terrain_matching', the house would be deformed to fit the change in land.
          // That's best for roads so lets stay 'rigid' for now.
        "projection": "rigid",

          // The kind of element we are spawning. This one is most likely what you want.
          // There's 'minecraft:legacy_single_pool_element' but that swaps the behavior of
          // Air and Structure Void in your piece as well as change the attachment mechanism.
          // It's only for old Vanilla Jigsaw Structures so don't use it. Stick with non-legacy.
        "element_type": "minecraft:single_pool_element"
      }
    }
  ]
}