fix syntax

agent.py

@@ -1,4 +1,5 @@
 import math
+import os
 
 import numexpr
 from langchain_community.document_loaders import ArxivLoader
@@ -10,6 +11,8 @@ from smolagents import (
     tool,
 )
 
+hf_token = os.getenv("HUGGINGFACEHUB_API_TOKEN")
+
 
 @tool
 def calculator(expression: str) -> str:
@@ -21,6 +24,8 @@ def calculator(expression: str) -> str:
     Examples:
         "37593 * 67" for "37593 times 67"
         "37593**(1/5)" for "37593^(1/5)"
+    Args:
+        expression: the expression to be compute
     """
     local_dict = {"pi": math.pi, "e": math.e}
     return str(
@@ -36,6 +41,8 @@ def calculator(expression: str) -> str:
 def arxiv_search_tool(query: str) -> str:
     """
     Searches Arxiv and returns a summary or full text of the given topic, along with the page URL.
+    Args:
+        query: the topic to be searched
     """
     doc = ArxivLoader(query=query, load_max_docs=1).load()
     if len(doc) > 0:
@@ -49,7 +56,7 @@ tools = [calculator, arxiv_search_tool, DuckDuckGoSearchTool, WikipediaSearchToo
 
 model_id = "Qwen/Qwen3-30B-A3B"
 model = InferenceClientModel(
-    model_id=model_id, token="MY_HUGGINGFACEHUB_API_TOKEN"
+    model_id=model_id, token=hf_token
 )  # You can choose to not pass any model_id to InferenceClientModel to use a default model
 agent = CodeAgent(
     model=model,