added system message to ensure better response

Signed-off-by: Erik Jan de Wit <erikjan.dewit@gmail.com>

Author: edewit

roq-editor/runtime/src/main/java/io/quarkiverse/roq/editor/runtime/devui/RoqEditorJsonRPCService.java

@@ -42,6 +42,10 @@ public class RoqEditorJsonRPCService {
             "markdown", "md",
             "html", "html");
 
+    private static final String SYSTEM_MESSAGE = "You are a blog content writer. Generate blog post body content in Markdown based on the user's request. Do not include frontmatter or "
+            +
+            "metadata - only the content. Start directly with the content, no preamble.";
+
     @Inject
     private Site site;
 
@@ -399,6 +403,7 @@ public boolean isError() {
     public CompletionStage<Map<String, String>> generateContent(String message) {
         if (assistant.isPresent()) {
             return assistant.get().assistBuilder()
+                    .systemMessage(SYSTEM_MESSAGE)
                     .userMessage(message)
                     .responseType(ContentResponse.class)
                     .assist();