anchor.diff:  
   * `result` (required, object)
       * `sessionId` (required, string). Session identifier.
  -
  -The following example shows a typical response while invoking the operation connect (that doesn’t return anything):
  -
  -+ Body (application/json)
  -
  -        {
  -          "jsonrpc": "2.0",
  -          "result": {
  -            "sessionId": "c93e5bf0-4fd0-4888-9411-765ff5d89b93"
  -          },
  -          "id": 2
  +    * `value` (optional, object). Additional object which describes the result of the `Invoke` operation. For example, in a `WebRtcEndpoint` this field is the SDP response (WebRTC SDP negotiation).
  +
  +The following example shows a typical response while invoking the operation connect:
  +
  ++ Body (application/json)
  +
  +        {
  +            "id": 5,
  +            "result": {
  +                "sessionId": "bd4d6227-0463-4d52-b1c3-c71f0be68466"
  +            },
  +            "jsonrpc": "2.0"
           }
   
   ## Group Release
  
positive.code:     * `value` (required, number). Identifier of the created media element.
      * `sessionId` (required, string). Session identifier.
  
  The following example shows a typical response to a create message:
  
  + Body (application/json)
  
          {
            "jsonrpc": "2.0",
            "id": 1,
            "result": {
              "value": "442352747",
              "sessionId": "c93e5bf0-4fd0-4888-9411-765ff5d89b93"
            }
          }
  
  ## Group Invoke
  
  Invoke message requests the invocation of an operation in the specified object. The parameter object indicates the id of the object in which the operation will be invoked. The parameter operation carries the name of the operation to be executed. Finally, the parameter operationParams has the parameters needed to execute the operation. The object specified has to understand the
  
  ### Request
  
  
negative.code: + Body (application/json)
  
          {
              "id": 38,
              "result": {
                  "sessionId": "bd4d6227-0463-4d52-b1c3-c71f0be68466"
              },
              "jsonrpc": "2.0"
          }
  
  ## Group OnEvent
  
  When a client is `subscribed` to a type of events in an object, the server sends an onEvent request each time an event of that type is fired in the object. This is possible because the Stream Oriented open API is implemented with WebSockets and there is a full duplex channel between client and server.
  
  ### Request
  
  