Update app.py

app.py

@@ -14,7 +14,7 @@ from langchain_community.tools.arxiv.tool import ArxivQueryRun
 from langchain_community.utilities.arxiv import ArxivAPIWrapper
 
 from langgraph.graph import StateGraph, END
-from langgraph.prebuilt import ToolInvocation
+
 from langchain_core.messages import BaseMessage, FunctionMessage, HumanMessage, AIMessage
 from langchain_openai import ChatOpenAI
 
@@ -31,11 +31,17 @@ if not OPENROUTER_API_KEY:
     print("Warning: OPENROUTER_API_KEY not found in .env file. The LLM will not function.")
 
 # --- Tool Setup ---
-tavily_tool = TavilySearchResults(max_results=3, api_key=TAVILY_API_KEY if TAVILY_API_KEY else "placeholder_tavily_key") # Add placeholder if not found
+tools = []
+if TAVILY_API_KEY:
+    tavily_tool = TavilySearchResults(max_results=3, api_key=TAVILY_API_KEY)
+    tools.append(tavily_tool)
+else:
+    print("Warning: TAVILY_API_KEY not found in .env file. TavilySearchResults tool will not be available.")
+
 wikipedia_tool = WikipediaQueryRun(api_wrapper=WikipediaAPIWrapper(top_k_results=2, doc_content_chars_max=2000))
+tools.append(wikipedia_tool)
 arxiv_tool = ArxivQueryRun(api_wrapper=ArxivAPIWrapper(top_k_results=2, doc_content_chars_max=2000))
-
-tools = [tavily_tool, wikipedia_tool, arxiv_tool]
+tools.append(arxiv_tool)
 
 # --- LangGraph Agent Definition ---
 class AgentState(TypedDict):
@@ -341,5 +347,4 @@ if __name__ == "__main__":
     print("-"*(60 + len(" App Starting ")) + "\n")
 
     print("Launching Gradio Interface for LangGraph GAIA Agent Evaluation...")
-    demo.launch(debug=True, share=False)
-
+    demo.launch(debug=True, share=False)