diff --git a/tools/standalone_llm_tool.py b/tools/standalone_llm_tool.py
index 3c13291..8b9479b 100644
--- a/tools/standalone_llm_tool.py
+++ b/tools/standalone_llm_tool.py
@@ -9,6 +9,9 @@ import urllib.error
 class StandaloneLLMTool(BaseTool):
     def __init__(self):
         self.client = OpenAI(api_key=os.environ.get("OPENAI_API_KEY"))
+        self.copilot_url = os.getenv("COPILOT_API_URL")
+        if not self.copilot_url:
+            logging.warning("COPILOT_API_URL environment variable not set. call_external_copilot will not function.")
 
     def clear(self):
         pass
@@ -55,28 +58,27 @@ class StandaloneLLMTool(BaseTool):
                             "prompt": {
                                 "type": "string",
                                 "description": "The plain text prompt to send to the external copilot."
-                            },
-                            "url": {
-                                "type": "string",
-                                "description": "The URL of the external copilot's API endpoint (e.g., 'http://localhost:8000/copilot')."
                             }
                         },
-                        "required": ["prompt", "url"]
+                        "required": ["prompt"]
                     }
                 },
                 "_tags": ["copilot", "external", "http"]
             }
         ]
 
-    def _call_external_copilot(self, prompt: str, url: str):
-        logging.info(f"Calling external copilot at URL: {url} with prompt: {prompt[:50]}...")
-        if not url.startswith('http://') and not url.startswith('https://'):
-            error_message = f"Invalid URL scheme for external copilot: {url}. URL must start with http:// or https://"
+    def _call_external_copilot(self, prompt: str):
+        if not self.copilot_url:
+            return "Error: COPILOT_API_URL environment variable is not set. Cannot call external copilot."
+
+        logging.info(f"Calling external copilot at URL: {self.copilot_url} with prompt: {prompt[:50]}...")
+        if not self.copilot_url.startswith('http://') and not self.copilot_url.startswith('https://'):
+            error_message = f"Invalid URL scheme for external copilot: {self.copilot_url}. URL must start with http:// or https://"
             logging.error(error_message)
             return error_message
         try:
             req = urllib.request.Request(
-                url,
+                self.copilot_url,
                 data=prompt.encode('utf-8'),
                 headers={'Content-Type': 'text/plain; charset=utf-8', 'User-Agent': 'DualAICopilot/0.1'},
                 method='POST'
@@ -87,7 +89,7 @@ class StandaloneLLMTool(BaseTool):
                     logging.info(f"Received response from external copilot: {response_data[:100]}...")
                     return response_data
                 else:
-                    error_message = f"External copilot at {url} returned an error: {response.status} {response.reason}"
+                    error_message = f"External copilot at {self.copilot_url} returned an error: {response.status} {response.reason}"
                     logging.error(error_message)
                     return error_message # Return error as string
         except urllib.error.HTTPError as e:
@@ -96,15 +98,15 @@ class StandaloneLLMTool(BaseTool):
                 error_body = e.read().decode('utf-8', 'replace') # Added error decoding fallback
             except Exception:
                 pass 
-            error_message = f"HTTP Error {e.code} calling external copilot at {url}: {e.reason}. Response: {error_body}"
+            error_message = f"HTTP Error {e.code} calling external copilot at {self.copilot_url}: {e.reason}. Response: {error_body}"
             logging.error(error_message)
             return error_message
         except urllib.error.URLError as e:
-            error_message = f"URL Error calling external copilot at {url}: {e.reason}"
+            error_message = f"URL Error calling external copilot at {self.copilot_url}: {e.reason}"
             logging.error(error_message)
             return error_message
         except Exception as e:
-            error_message = f"An unexpected error occurred while calling external copilot at {url}: {str(e)}"
+            error_message = f"An unexpected error occurred while calling external copilot at {self.copilot_url}: {str(e)}"
             logging.error(error_message)
             return error_message
 
@@ -114,7 +116,7 @@ class StandaloneLLMTool(BaseTool):
             max_tokens = kwargs.get("max_tokens", 16384) # Default from spec
             return self.call_external_llm(kwargs.get("prompt"), model, max_tokens)
         elif function_name == "call_external_copilot":
-            return self._call_external_copilot(kwargs.get("prompt"), kwargs.get("url"))
+            return self._call_external_copilot(kwargs.get("prompt"))
         else:
             error_message = f"Unknown function: {function_name}"
             logging.error(error_message)