diff --git a/openevolve/config.py b/openevolve/config.py
index 1a1a19338..303e2941c 100644
--- a/openevolve/config.py
+++ b/openevolve/config.py
@@ -40,7 +40,6 @@ class LLMConfig(LLMModelConfig):
 
     # API configuration
     api_base: str = "https://api.openai.com/v1"
-    name: str = "gpt-4o"
 
     # Generation parameters
     system_message: Optional[str] = "system_message"
@@ -60,10 +59,10 @@ class LLMConfig(LLMModelConfig):
     evaluator_models: List[LLMModelConfig] = field(default_factory=lambda: [])
 
     # Backwardes compatibility with primary_model(_weight) options
-    primary_model: str = "gemini-2.0-flash-lite"
-    primary_model_weight: float = 0.8
-    secondary_model: str = "gemini-2.0-flash"
-    secondary_model_weight: float = 0.2
+    primary_model: str = None
+    primary_model_weight: float = None
+    secondary_model: str = None
+    secondary_model_weight: float = None
 
     def __post_init__(self):
         """Post-initialization to set up model configurations"""
diff --git a/openevolve/llm/openai.py b/openevolve/llm/openai.py
index c146ecc0c..47a6aba2f 100644
--- a/openevolve/llm/openai.py
+++ b/openevolve/llm/openai.py
@@ -107,4 +107,8 @@ async def _call_api(self, params: Dict[str, Any]) -> str:
         response = await loop.run_in_executor(
             None, lambda: self.client.chat.completions.create(**params)
         )
+        # Logging of system prompt, user message and response content
+        logger = logging.getLogger(__name__)
+        logger.debug(f"API parameters: {params}")
+        logger.debug(f"API response: {response.choices[0].message.content}")
         return response.choices[0].message.content