diff --git a/GithubPRReviewBot/Services/LlmReviewService.cs b/GithubPRReviewBot/Services/LlmReviewService.cs
index 6a69e17..71bf6a4 100644
--- a/GithubPRReviewBot/Services/LlmReviewService.cs
+++ b/GithubPRReviewBot/Services/LlmReviewService.cs
@@ -21,7 +21,8 @@ public async Task<ChatResult> LlmReviewDiff(string diff)
             var chatRequest = new ChatRequest()
             {
                 Messages =
-                [
+                [   
+                    new ChatMessage(ChatMessageRole.System, $"You are an AI-powered code reviewer."),
                     new ChatMessage(ChatMessageRole.User, $"Please review the following code diff: {diff}")
                 ],
                 Model = model,