json_schema: {
      "definitions": {
          "user": {
              "$schema": "http://json-schema.org/draft-04/schema",
              "definitions": {
                  "created_at": {
                      "description": "when user was created",
                      "format": "date-time",
                      "type": [
                          "string"
                      ]
                  },
                  "id": {
                      "description": "unique identifier of user",
                      "format": "uuid",
                      "readOnly": true,
                      "type": [
                          "string"
                      ]
                  },
                  "identity": {
                      "anyOf": [
                          {
                              "$ref": "#/definitions/user/definitions/id"
                          },
                          {
                              "$ref": "#/definitions/user/definitions/name"
                          }
                      ]
                  },
                  "name": {
                      "description": "unique name of user",
                      "readOnly": true,
                      "type": [
                          "string"
                      ]
                  },
                  "updated_at": {
                      "description": "when user was updated",
                      "format": "date-time",
                      "type": [
                          "string"
                      ]
                  }
              },
              "description": "FIXME",
              "links": [
                  {
                      "description": "Create a new user.",
                      "href": "/users",
                      "method": "POST",
                      "rel": "create",
                      "schema": {
                          "properties": {},
                          "type": [
                              "object"
                          ]
                      },
                      "title": "Create"
                  },
                  {
                      "description": "Delete an existing user.",
                      "href": "/users/{(%23%2Fdefinitions%2Fuser%2Fdefinitions%2Fidentity)}",
                      "method": "DELETE",
                      "rel": "destroy",
                      "title": "Delete"
                  },
                  {
                      "description": "Info for existing user.",
                      "href": "/users/{(%23%2Fdefinitions%2Fuser%2Fdefinitions%2Fidentity)}",
                      "method": "GET",
                      "rel": "self",
                      "title": "Info"
                  },
                  {
                      "description": "List existing users.",
                      "href": "/users",
                      "method": "GET",
                      "rel": "instances",
                      "title": "List"
                  },
                  {
                      "description": "Update an existing user.",
                      "href": "/users/{(%23%2Fdefinitions%2Fuser%2Fdefinitions%2Fidentity)}",
                      "method": "PATCH",
                      "rel": "update",
                      "schema": {
                          "properties": {},
                          "type": [
                              "object"
                          ]
                      },
                      "title": "Update"
                  }
              ],
              "properties": {
                  "created_at": {
                      "$ref": "#/definitions/user/definitions/created_at"
                  },
                  "id": {
                      "$ref": "#/definitions/user/definitions/id"
                  },
                  "name": {
                      "$ref": "#/definitions/user/definitions/name"
                  },
                  "updated_at": {
                      "$ref": "#/definitions/user/definitions/updated_at"
                  }
              },
              "stability": "prototype",
              "strictProperties": true,
              "title": "FIXME - User",
              "type": [
                  "object"
              ]
          }
      },
      "description": "例のAPI",
      "links": [
          {
              "href": "http://api.example.com",
              "rel": "self"
          }
      ],
      "properties": {
          "user": {
              "$ref": "#/definitions/user"
          }
      },
      "title": "Example API",
      "type": [
          "object"
      ]
  }