diff --git a/Daraja.App/Program.cs b/Daraja.App/Program.cs
index 2d6fda6..1e3fe3b 100644
--- a/Daraja.App/Program.cs
+++ b/Daraja.App/Program.cs
@@ -22,12 +22,15 @@ static async Task Main(string[] args)
             var grantType = config["GrantType"];
             var passKey = config["PassKey"];
 
-            var gateway = new DarajaGateway(endpoint, consumerKey, consumerSecret, passKey);
+            if (endpoint != null && consumerKey != null && consumerSecret != null && passKey != null)
+            {
+                var gateway = new DarajaGateway(endpoint, consumerKey, consumerSecret, passKey);
 
-            var darajaClient = await gateway.GetDarajaClientAsync();
+                var darajaClient = await gateway.GetDarajaClientAsync();
 
-            if (darajaClient != null)
-                await MakeStkPush(gateway, darajaClient);
+                if (darajaClient != null)
+                    await MakeStkPush(gateway, darajaClient);
+            }
         }
 
         private static async Task MakeStkPush(DarajaGateway darajaGateway, DarajaClient darajaClient)
diff --git a/MpesaDaraja/Interfaces/IDarajaClient.cs b/MpesaDaraja/Interfaces/IDarajaClient.cs
index f07d7e3..73c7dc2 100644
--- a/MpesaDaraja/Interfaces/IDarajaClient.cs
+++ b/MpesaDaraja/Interfaces/IDarajaClient.cs
@@ -47,7 +47,7 @@ internal interface IDarajaClient
         /// <param name="pushResponse">Response from initiating the STK Push</param>
         /// <param name="stkData">The <see cref="StkData"/> object used to initiate the stk push</param>
         /// <returns></returns>
-        Task<(bool isCompleted, PushQueryResponse response)> QueryStkPushStatus(PushResponse pushResponse,
+        Task<(bool isCompleted, PushQueryResponse? pushQueryResponse)> QueryStkPushStatus(PushResponse pushResponse,
             StkData stkData);
 
     }
diff --git a/MpesaDaraja/Models/PushQueryResponse.cs b/MpesaDaraja/Models/PushQueryResponse.cs
index 19c5e0e..4bb26e0 100644
--- a/MpesaDaraja/Models/PushQueryResponse.cs
+++ b/MpesaDaraja/Models/PushQueryResponse.cs
@@ -12,21 +12,42 @@ namespace MpesaDaraja.Models
     /// </summary>
     public class PushQueryResponse
     {
+        /// <summary>
+        ///     This is a Numeric status code that indicates the status of the transaction submission. 0 means successful submission and any other code means an error occurred. 
+        /// </summary>
         [JsonProperty("ResponseCode")]
         public string? ResponseCode { get; set; }
 
+        /// <summary>
+        ///     Response description is an acknowledgment message from the API that gives the status of the request submission usually maps to a specific ResponseCode value.
+        ///     It can be a Success submission message or an error description
+        /// </summary>
         [JsonProperty("ResponseDescription")]
         public string? ResponseDescription { get; set; }
 
+        /// <summary>
+        ///     This is a global unique Identifier for any submitted payment request.
+        /// </summary>
         [JsonProperty("MerchantRequestID")]
         public string? MerchantRequestId { get; set; }
 
+        /// <summary>
+        ///     This is a global unique identifier of the processed checkout transaction request.
+        /// </summary>
         [JsonProperty("CheckoutRequestID")]
         public string? CheckoutRequestId { get; set; }
 
+        /// <summary>
+        ///     This is a numeric status code that indicates the status of the transaction processing.
+        ///     0 means successful processing and any other code means an error occurred or the transaction failed.
+        /// </summary>
         [JsonProperty("ResultCode")]
         public string? ResultCode { get; set; }
 
+        /// <summary>
+        ///     Result description is a message from the API that gives the status of the request processing, usually maps to a specific ResultCode value.
+        ///     It can be a Success processing message or an error description message.
+        /// </summary>
         [JsonProperty("ResultDesc")]
         public string? ResultDesc { get; set; }
     }
diff --git a/MpesaDaraja/Models/PushResponse.cs b/MpesaDaraja/Models/PushResponse.cs
index 8c1d12d..032c95e 100644
--- a/MpesaDaraja/Models/PushResponse.cs
+++ b/MpesaDaraja/Models/PushResponse.cs
@@ -10,7 +10,7 @@ namespace MpesaDaraja.Models
     /// <summary>
     ///     Result after initiating an stk push
     /// </summary>
-    public class PushResult
+    public class PushResponse
     {
         /// <summary>
         ///     This is a global unique Identifier for any submitted payment request.
diff --git a/MpesaDaraja/Models/StkData.cs b/MpesaDaraja/Models/StkData.cs
index 6a59a34..d6c1664 100644
--- a/MpesaDaraja/Models/StkData.cs
+++ b/MpesaDaraja/Models/StkData.cs
@@ -7,6 +7,9 @@
 
 namespace MpesaDaraja.Models
 {
+    /// <summary>
+    ///     Defines the class for initiating online payment on behalf of a customer.
+    /// </summary>
     public class StkData
     {
         /// <summary>
@@ -77,6 +80,9 @@ public class StkData
         [JsonProperty("TransactionDesc")]
         public string? TransactionDesc { get; set; }
 
+        /// <summary>
+        ///     Creates an instance of the <see cref="StkData"/> class
+        /// </summary>
         public StkData()
         {
             Timestamp = DateTime.Now.ToString("yyyyMMddHHmmss");