DialogFlow CX integration with Genesys or CX One

[MattF]

Hi everyone

I'm trying to connect DialogFlow CX chat with some CX tools like Nice or Genesys. And the chat is working. 
But my problem is to receive parameters from the platform and the way to use it in DialogFlow.

Here an example of the input i receive on log activity.
How can i use the parameter firstName on DialogFlow ? 

{
  "insertId": "-cggsxvqhcamq",
  "jsonPayload": {
    "queryParams": {
      "payload": {
        "context": "{\n  \"id\": \"information\",\n  \"lifespan\": \"2\",\n  \"parameters\": {\n    \"MSDynaContactId\": \"07cf2edb-ab48-ed11-bba2\",\n    \"firstName\": \"FN\",\n    \"lastName\": \"Kimura\",\n    \"segment\": \"SILVER\",\n    \"OvaloContactId\": \"OV0002\",\n    \"mobilePhone\": \"6346373\",\n    \"emailAddress1\": \"takashikimura.customer@gmail.com\",\n    \"facebook\": \"\"\n  }\n}"
      },
      "parameters": {}
    },
    "queryInput": {
      "languageCode": "fr",
      "text": {
        "text": "OV0002"
      }
    },
    "session": "projects/profile-bot-dohn/locations/europe-west3/agents/3136149e-42f2-4ac5-ab47-/environments/draft/sessions/BusNo--"
  },
  "resource": {
    "type": "global",
    "labels": {
      "project_id": "profile-bot-dohn"
    }
  },
  "timestamp": "2022-12-13T13:23:25.801205Z",
  "severity": "INFO",
  "labels": {
    "session_id": "BusNo--",
    "agent_id": "3136149e-42f2-4ac5-ab47-",
    "location_id": "europe-west3"
  },
  "logName": "projects/profile-bot-dohn/logs/dialogflow-runtime.googleapis.com%2Frequests",
  "receiveTimestamp": "2022-12-13T13:23:26.476085542Z"
}

thank you for your help