update agent

agent.py

@@ -9,9 +9,12 @@ from langchain_community.tools.tavily_search import TavilySearchResults
 from langchain_community.document_loaders import WikipediaLoader, ArxivLoader
 from langchain_core.messages import SystemMessage, HumanMessage
 from langchain_core.tools import tool
+from langchain_groq import ChatGroq
 
 load_dotenv()
 
+
+
 # ------------------- TOOL DEFINITIONS -------------------
 
 @tool
@@ -82,7 +85,10 @@ def build_graph(provider: str = "groq"):
     if provider == "google":
         llm = ChatGoogleGenerativeAI(model="gemini-2.0-flash", temperature=0)
     elif provider == "groq":
-        llm = ChatGroq(model="qwen-qwq-32b", temperature=0)
+        groq_key = os.getenv("GROQ_API_KEY")
+        if not groq_key:
+            raise ValueError("GROQ_API_KEY is not set.")
+        llm = ChatGroq(model="qwen-qwq-32b", temperature=0, api_key=groq_key)
     elif provider == "huggingface":
         llm = ChatHuggingFace(
             llm=HuggingFaceEndpoint(