diff --git a/OpenAI-DotNet/Assistants/AssistantExtensions.cs b/OpenAI-DotNet/Assistants/AssistantExtensions.cs
index 5db2a6cf..5e3789a7 100644
--- a/OpenAI-DotNet/Assistants/AssistantExtensions.cs
+++ b/OpenAI-DotNet/Assistants/AssistantExtensions.cs
@@ -187,13 +187,8 @@ public static async Task<bool> DeleteFileAsync(this AssistantResponse assistant,
         /// <returns>Tool output result as <see cref="string"/></returns>
         public static string InvokeToolCall(this AssistantResponse assistant, ToolCall toolCall)
         {
-            var tool = assistant.Tools.FirstOrDefault(tool => toolCall.Type == "function" && tool.Function.Name == toolCall.FunctionCall.Name);
-
-            if (tool == null)
-            {
+            var tool = assistant.Tools.FirstOrDefault(tool => toolCall.Type == "function" && tool.Function.Name == toolCall.FunctionCall.Name) ??
                 throw new InvalidOperationException($"Failed to find a valid tool for [{toolCall.Id}] {toolCall.Type}");
-            }
-
             tool.Function.Arguments = toolCall.FunctionCall.Arguments;
             return tool.InvokeFunction();
         }
@@ -207,13 +202,8 @@ public static string InvokeToolCall(this AssistantResponse assistant, ToolCall t
         /// <returns>Tool output result as <see cref="string"/></returns>
         public static async Task<string> InvokeToolCallAsync(this AssistantResponse assistant, ToolCall toolCall, CancellationToken cancellationToken = default)
         {
-            var tool = assistant.Tools.FirstOrDefault(tool => toolCall.Type == "function" && tool.Function.Name == toolCall.FunctionCall.Name);
-
-            if (tool == null)
-            {
+            var tool = assistant.Tools.FirstOrDefault(tool => toolCall.Type == "function" && tool.Function.Name == toolCall.FunctionCall.Name) ??
                 throw new InvalidOperationException($"Failed to find a valid tool for [{toolCall.Id}] {toolCall.Type}");
-            }
-
             tool.Function.Arguments = toolCall.FunctionCall.Arguments;
             return await tool.InvokeFunctionAsync(cancellationToken).ConfigureAwait(false);
         }