Used Guid - No lookup Azure Function

UsedGuidBasicInput.cs

using System.Net;

public class UserInput
{
    public string Guid {get;set;}
    public string UsedBy { get;set;}
}

public class UsedGuidDocument
{   
    public string id { get; set; } // DocumentDB default id convention
    public string UsedBy { get;set;}
}

public static bool UserInputIsValid(UserInput userData)
{
    return !(userData == null || userData.Guid == null || userData.UsedBy == null);
}


public static HttpResponseMessage Run(HttpRequestMessage req, TraceWriter log,
    out object doc, out string guidQueue)
{
    // prep error case initially
    var responseMsg = "Please pass a Guid and UsedBy in the request body";
    var statusCode = HttpStatusCode.BadRequest;
    
    var userData = req.Content.ReadAsAsync<UserInput>().Result;
    
    if (UserInputIsValid(userData))
    {
        doc = new UsedGuidDocument { id = userData.Guid, UsedBy = userData.UsedBy };
        statusCode = HttpStatusCode.OK;
        responseMsg = $"Success {userData.Guid} - {userData.UsedBy}";
        guidQueue = responseMsg;
    }
    else
    {
        doc = null; // because doc is `out` we need to set it to something
        guidQueue = null; //same
    }
    
    return req.CreateResponse(statusCode, responseMsg);
}