diff --git a/ra_aid/agents/ciayn_agent.py b/ra_aid/agents/ciayn_agent.py
index 0c1b85d..a9cde81 100644
--- a/ra_aid/agents/ciayn_agent.py
+++ b/ra_aid/agents/ciayn_agent.py
@@ -20,10 +20,17 @@ class CiaynAgent:
 \"\"\""""
         return info
 
-    def __init__(self, model, tools: list):
-        """Initialize the agent with a model and list of tools."""
+    def __init__(self, model, tools: list, max_history_messages: int = 50):
+        """Initialize the agent with a model and list of tools.
+        
+        Args:
+            model: The language model to use
+            tools: List of tools available to the agent
+            max_history_messages: Maximum number of messages to keep in chat history
+        """
         self.model = model
         self.tools = tools
+        self.max_history_messages = max_history_messages
         self.available_functions = []
         for t in tools:
             self.available_functions.append(self._get_function_info(t.func))
@@ -91,6 +98,25 @@ Output **ONLY THE CODE** and **NO MARKDOWN BACKTICKS**"""
             }
         }
 
+    def _trim_chat_history(self, initial_messages: List[Any], chat_history: List[Any]) -> List[Any]:
+        """Trim chat history to maximum length while preserving initial messages.
+        
+        Only trims the chat_history portion while preserving all initial messages.
+        Returns the concatenated list of initial_messages + trimmed chat_history.
+        
+        Args:
+            initial_messages: List of initial messages to preserve
+            chat_history: List of chat messages that may be trimmed
+            
+        Returns:
+            List[Any]: Concatenated initial_messages + trimmed chat_history
+        """
+        if len(chat_history) <= self.max_history_messages:
+            return initial_messages + chat_history
+            
+        # Keep last max_history_messages from chat_history
+        return initial_messages + chat_history[-self.max_history_messages:]
+
     def stream(self, messages_dict: Dict[str, List[Any]], config: Dict[str, Any] = None) -> Generator[Dict[str, Any], None, None]:
         """Stream agent responses in a format compatible with print_agent_output."""
         initial_messages = messages_dict.get("messages", [])
@@ -102,7 +128,7 @@ Output **ONLY THE CODE** and **NO MARKDOWN BACKTICKS**"""
             base_prompt = self._build_prompt(None if first_iteration else last_result)
             chat_history.append(HumanMessage(content=base_prompt))
             
-            full_history = initial_messages + chat_history
+            full_history = self._trim_chat_history(initial_messages, chat_history)
             response = self.model.invoke(full_history)
                 
             try: