minecraft-bedrock-json-schemas/source/general/array_3_number.json

{
  "$id": "general.array.number.3",
  "type": "array",
  "title": "Array Of 3 Items",
  "description": "An array of 3 numbers",
  "examples": [[0, 1, 2]],
  "items": [
    { "type": "number", "description": "An number", "title": "X" },
    { "type": "number", "description": "An number", "title": "Y" },
    { "type": "number", "description": "An number", "title": "Z" }
  ]
}