don't save standard prompt

evaluation_logic.py

@@ -64,7 +64,7 @@ def save_evaluation(inference_api, model_name, prompt_format, custom_prompt, met
         "inference_api": inference_api,
         "model_name": model_name,
         "prompt_format": prompt_format,
-        "custom_prompt": str(custom_prompt),
+        "custom_prompt": str(custom_prompt) if prompt_format.startswith("custom") else "",
         "timestamp": datetime.now().isoformat()
     }