use this https://www.nuget.org/packages/Google.Apis.Dialogflow.v2/ it's a nuget specifically for dialogflow, and it's so easy to see the intents like this.
public GoogleCloudDialogflowV2WebhookResponse Post(GoogleCloudDialogflowV2WebhookRequest obj)
{
string Location = string.Empty;
switch (obj.QueryResult.Intent.DisplayName)
{
case "getstock":
Location = obj.QueryResult.Parameters["Location"].ToString();
break;
}
var response = new GoogleCloudDialogflowV2WebhookResponse()
{
FulfillmentText = $"The stock at {Location} is valuing Rs. 31 Lakhs \n And consists of items such as slatwall, grid and new pillar. The detailed list of the same has been email to you",
Source = "API.AI"
};
return response;
}
from this answer: dialogflow simple fulfillment webhook in c# not working