Minecraft wiki entry for Data_pack, associated text: The root object.
 pack: Holds the data pack information.
 description: A JSON text that appears when hovering over the data pack's name in the list given by the /datapack list command, or when viewing the pack in the Create World screen.
 pack_format: Pack version: If this number does not match the current required number, the data pack displays a warning and requires additional confirmation to load the pack. Requires 4 for 1.13–1.14.4. Requires 5 for 1.15–1.16.1. Requires 6 for 1.16.2–1.16.5. Requires 7 for 1.17 and 1.17.1. Requires 8 for 1.18 and 1.18.1. Requires 9 for 1.18.2. Requires 10 for 1.19.