curl --request GET \
  --url https://sandbox.tight.com/v6/categories \
  --header 'Authorization: Bearer <token>'

{
  "data": {
    "expense": [
      {
        "id": "gla_167243195",
        "name": "Wages",
        "status": "ACTIVE",
        "iconUrl": "https://cdn.sandbox.tight.com/icons/expenseCategories/payroll.svg",
        "children": [
          {
            "id": "gla_167243196",
            "name": "Officer(s) Salaries and Wages",
            "status": "ACTIVE",
            "iconUrl": "https://cdn.sandbox.tight.com/icons/expenseCategories/payroll.svg",
            "customData": {
              "internal_key": "some_internal_key",
              "some_other_field": 23434
            }
          }
        ],
        "customData": {
          "internal_key": "some_internal_key",
          "some_other_field": 23434
        }
      }
    ],
    "revenue": [
      {
        "id": "gla_167243195",
        "name": "Wages",
        "status": "ACTIVE",
        "iconUrl": "https://cdn.sandbox.tight.com/icons/expenseCategories/payroll.svg",
        "children": [
          {
            "id": "gla_167243196",
            "name": "Officer(s) Salaries and Wages",
            "status": "ACTIVE",
            "iconUrl": "https://cdn.sandbox.tight.com/icons/expenseCategories/payroll.svg",
            "customData": {
              "internal_key": "some_internal_key",
              "some_other_field": 23434
            }
          }
        ],
        "customData": {
          "internal_key": "some_internal_key",
          "some_other_field": 23434
        }
      }
    ],
    "transfer": [
      {
        "id": "gla_167243196",
        "name": "Officer(s) Salaries and Wages",
        "status": "ACTIVE",
        "iconUrl": "https://cdn.sandbox.tight.com/icons/expenseCategories/payroll.svg",
        "customData": {
          "internal_key": "some_internal_key",
          "some_other_field": 23434
        }
      }
    ]
  }
}