feat: set frequency penalty to 1 for gpt-4o (#3962)

letta/agents/helpers.py

@@ -222,6 +222,7 @@ def _safe_load_tool_call_str(tool_call_args_str: str) -> dict:
             # Load it again - this is due to sometimes Anthropic returning weird json @caren
             tool_args = json.loads(tool_args)
     except json.JSONDecodeError:
+        logger.error("Failed to JSON decode tool call argument string: %s", tool_call_args_str)
         tool_args = {}
 
     return tool_args

letta/schemas/providers/openai.py

@@ -142,7 +142,7 @@ class OpenAIProvider(Provider):
         """This function is used to tune LLMConfig parameters to improve model performance."""
 
         # gpt-4o-mini has started to regress with pretty bad emoji spam loops (2025-07)
-        if "gpt-4o-mini" in model_name or "gpt-4.1-mini" in model_name:
+        if "gpt-4o" in model_name or "gpt-4.1-mini" in model_name:
             llm_config.frequency_penalty = 1.0
         return llm_config