json_schema: {
      "description": "A **custom field** defines an abstract field that admissions staff can use to store arbitrary data about an applicant.  The data itself is stored in a **custom field answer**.",
      "links": [
          {
              "description": "List existing custom fields.",
              "href": "/api/v1/user_identities/:user_identity_id/programs/:program_id/custom_fields",
              "http_header": {
                  "x-api-key": "0123456789abcdef0123456789abcdef"
              },
              "method": "GET",
              "rel": "self",
              "title": "List"
          }
      ],
      "properties": {
          "custom_fields": {
              "items": {
                  "properties": {
                      "field_type": {
                          "description": "The type of data that this field stores.",
                          "enum": [
                              "boolean",
                              "number",
                              "date",
                              "string",
                              "select"
                          ],
                          "example": "select",
                          "type": "string"
                      },
                      "id": {
                          "description": "Unique identifier for this custom field.",
                          "example": 4,
                          "type": "integer"
                      },
                      "label": {
                          "description": "Human-readable name of this custom field.",
                          "example": "Preferred house",
                          "type": "string"
                      },
                      "options": {
                          "description": "When `field_type` is `\"select\"`, this defines the list of allowed values for the field.  Otherwise, this is `null`.",
                          "example": [
                              "Gryffindor",
                              "Hufflepuff",
                              "Ravenclaw",
                              "Slytherin"
                          ],
                          "items": {
                              "type": "string"
                          },
                          "type": [
                              "array",
                              "null"
                          ]
                      }
                  },
                  "type": "object"
              },
              "type": "array"
          },
          "href": {
              "description": "Hypertext reference to this resource.",
              "example": "/api/v1/user_identities/1/programs/42023191739237/custom_fields",
              "pattern": "/api/v1/user_identities/\\d+/programs/\\d+/custom_fields",
              "type": "string"
          }
      },
      "strictProperties": true,
      "title": "Custom Field",
      "type": "object"
  }