diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
index 78ae0ce..38e890a 100644
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -86,7 +86,7 @@ If you do not want to use LiteLLM at all, the framework allows you to inject any
 3. In the CLI wizard, select `custom_function` as the Model Type.
 4. Provide the path to `my_model.py` and the exact name of the function you wrote.
 
-The framework will dynamically import your file at runtime and use it exclusively for that agent's turns.
+The framework will dynamically import your file at runtime and use it exclusively for that agent's turns. Note that custom functions are executed with a timeout boundary (using the agent's configured `timeout` setting) to prevent infinite UI hangups.
 
 ## CI/CD and Robustness
 To ensure the framework remains stable as it grows, we maintain a comprehensive CI/CD pipeline using **GitHub Actions**. Every contribution is automatically tested against Python 3.13 for:
diff --git a/rooms/agent.py b/rooms/agent.py
index bb801ac..fec3a81 100644
--- a/rooms/agent.py
+++ b/rooms/agent.py
@@ -3,6 +3,7 @@
 import importlib.util
 import sys
 import os
+import concurrent.futures
 from typing import Optional, List, Dict, Any
 from .config import AgentConfig, ModelType
 
@@ -44,8 +45,13 @@ def _execute_custom_function(self, messages: List[Dict[str, str]]) -> str:
             inference_func = getattr(module, func_name)
             
             # We enforce standard (messages: List[Dict]) -> str signature for custom functions
-            response = inference_func(messages)
-            return str(response).strip()
+            with concurrent.futures.ThreadPoolExecutor(max_workers=1) as executor:
+                future = executor.submit(inference_func, messages)
+                try:
+                    response = future.result(timeout=self.config.timeout)
+                    return str(response).strip()
+                except concurrent.futures.TimeoutError:
+                    return f"[Timeout Error: The custom function '{func_name}' took too long to respond ({self.config.timeout}s)]"
             
         except AttributeError:
              return f"[Error: Function '{func_name}' not found in {file_path}]"