---
root1: { presence: required, structure: {
  field1: {
    presence: required,
    value: [X, Y, Z],
    comment: "field 1 description"
  }
}}
root2: { presence: required, structure: {
  field2: {
    presence: required,
    value: [X, Y, Z],
    comment: "field 1 description"
  }
}}
root3: { presence: required, structure: {
  field3: {
    presence: required,
    value: [X, Y, Z],
    comment: "field 1 description"
  }
}}
...