simple react agent

agent.py

@@ -0,0 +1,108 @@
+import re
+from dotenv import load_dotenv
+
+from langchain_core.tools import Tool, tool
+from langchain_core.messages import AnyMessage, HumanMessage, SystemMessage
+from langgraph.prebuilt import create_react_agent
+#from langgraph.graph import START, StateGraph
+#from langgraph.prebuilt import tools_condition, create_react_agent
+from langchain_community.tools import DuckDuckGoSearchRun
+from langchain_experimental.utilities import PythonREPL
+from langchain_google_genai import ChatGoogleGenerativeAI
+from langchain_ollama import ChatOllama
+from langfuse.langchain import CallbackHandler
+
+load_dotenv()
+langfuse_handler = CallbackHandler()
+
+# --- LLM ---
+#llm = ChatOllama(model="qwen3:8b", temperature=0)
+llm = ChatGoogleGenerativeAI(model='gemini-2.5-flash', temperature=0)
+
+# --- System Prompt ---
+with open('system_prompt.txt', 'r', encoding='utf-8') as f:
+    system_prompt = f.read()
+
+# --- Tools ---
+
+@tool
+def search_web(query: str) -> str:
+    """
+    A tool to perform a search for a query using the web
+
+    Args:
+        query (str): query to search on the web
+
+    Returns:
+        str: web search result
+    """
+    try:
+        search = DuckDuckGoSearchRun()
+        search.invoke(query)
+    except Exception as e:
+        return f"An error occured using search_web tool: {e}"
+
+# python REPL tool
+python_repl = PythonREPL()
+repl_tool = Tool(
+    name="python_repl",
+    description="A Python shell. Use this to execute python commands. "
+                "Input should be a valid python command. "
+                "If you want to see the output of a value, you should print it out with `print(...)`.",
+    func=python_repl.run,
+)
+
+@tool
+def reverse_string(text: str) -> str:
+    """
+    Reverse the order of characters in a text string
+
+    Args:
+        text (str): text string to reverse
+
+    Returns:
+        str: reversed text string
+    """
+    try:
+        return text[::-1]
+    except Exception as e:
+        return f"An error occured using reverse_string tool: {e}"
+
+
+tools = [search_web, reverse_string, repl_tool]
+
+# --- LangGraph ---
+agent = create_react_agent(
+    model=llm,  
+    tools=tools,  
+    prompt=system_prompt 
+)
+
+class GAIAAgent:
+    def __init__(self):
+        print("GAIAAgent initialized.")
+
+    def __call__(self, question: str) -> str:
+        print(f"Agent received question: {question}")
+
+        messages = agent.invoke(
+            {"messages": [
+                #SystemMessage(content=system),
+                HumanMessage(content=question)
+            ]},
+            config={
+                "callbacks": [langfuse_handler],
+                "recursion_limit": 10
+            }
+        )
+
+        # extract answer
+        final_message = messages['messages'][-1].content
+        match = re.search(r"(?<=FINAL ANSWER:\s).*", final_message)
+        if match:
+            final_answer = match.group(0)
+        else:
+            final_answer = f"I don't know\n'{final_message}'"
+
+        print(f"Agent returning answer: {final_answer}")
+        return final_answer

app.py

@@ -1,18 +1,9 @@
 import os
-import re
 import gradio as gr
 import requests
-import inspect
 import pandas as pd
 
-from typing import TypedDict, Annotated
-from langgraph.graph.message import add_messages
-from langchain_core.messages import AnyMessage, HumanMessage, AIMessage, SystemMessage
-from langgraph.prebuilt import ToolNode
-from langgraph.graph import START, StateGraph
-from langgraph.prebuilt import tools_condition
-from langchain_huggingface import HuggingFaceEndpoint, ChatHuggingFace
-from langchain_community.tools import DuckDuckGoSearchRun
+from agent import GAIAAgent
 
 # (Keep Constants as is)
 # --- Constants ---
@@ -20,83 +11,6 @@ DEFAULT_API_URL = "https://agents-course-unit4-scoring.hf.space"
 
 # --- Basic Agent Definition ---
 # ----- THIS IS WERE YOU CAN BUILD WHAT YOU WANT ------
-
-# Generate the AgentState and Agent graph
-class AgentState(TypedDict):
-    messages: Annotated[list[AnyMessage], add_messages]
-
-# --- Agent ---
-class GAIAAgent:
-    # --- LLM ---
-    llm = HuggingFaceEndpoint(
-        repo_id="Qwen/Qwen2.5-Coder-32B-Instruct"
-    )
-    chat = ChatHuggingFace(llm=llm, verbose=True)
-
-    # --- Tools ---
-    search_tool = DuckDuckGoSearchRun()
-    tools = [search_tool]
-
-    # --- System Prompt ---
-    system = """
-    You are a general AI assistant. I will ask you a question. Report your thoughts, and finish your 
-    answer with the following template: FINAL ANSWER: [YOUR FINAL ANSWER]. YOUR FINAL ANSWER should 
-    be a number OR as few words as possible OR a comma separated list of numbers and/or strings. If 
-    you are asked for a number, don't use comma to write your number neither use units such as $ or 
-    percent sign unless specified otherwise. If you are asked for a string, don't use articles, 
-    neither abbreviations (e.g. for cities), and write the digits in plain text unless specified 
-    otherwise. If you are asked for a comma separated list, apply the above rules depending of 
-    whether the element to be put in the list is a number or a string.
-    """.replace('\n', '')
-
-    def __init__(self):
-        self.build_graph()
-        print("GAIAAgent initialized.")
-
-    def build_graph(self):
-        self.chat_with_tools = self.chat.bind_tools(self.tools)
-
-        builder = StateGraph(AgentState)
-
-        def assistant(state: AgentState):
-            return {
-                "messages": [self.chat_with_tools.invoke(state["messages"])],
-            }
-
-        # Define nodes: these do the work
-        builder.add_node("assistant", assistant)
-        builder.add_node("tools", ToolNode(self.tools))
-
-        # Define edges: these determine how the control flow moves
-        builder.add_edge(START, "assistant")
-        builder.add_conditional_edges(
-            "assistant",
-            # If the latest message requires a tool, route to tools
-            # Otherwise, provide a direct response
-            tools_condition,
-        )
-        builder.add_edge("tools", "assistant")
-        self.graph = builder.compile()
-
-    def __call__(self, question: str) -> str:
-        print(f"Agent received question (first 50 chars): {question[:50]}...")
-
-        answer = self.graph.invoke(
-            {"messages": [
-                SystemMessage(content=self.system),
-                HumanMessage(content=question)
-            ]})
-        
-        # extract answer
-        match = re.search(r"(?<=FINAL ANSWER:\s).*", answer)
-        if match:
-            final_answer = match.group(0)
-        else:
-            final_answer = "I don't know"
-
-        print(f"Agent returning answer: {final_answer}")
-        return final_answer
-
 class BasicAgent:
     def __init__(self):
         print("BasicAgent initialized.")
@@ -163,9 +77,21 @@ def run_and_submit_all( profile: gr.OAuthProfile | None):
     for item in questions_data:
         task_id = item.get("task_id")
         question_text = item.get("question")
+        file_name = item.get("file_name")
         if not task_id or question_text is None:
             print(f"Skipping item with missing task_id or question: {item}")
             continue
+        if file_name:
+            # if question has an attached file, add the URL to the question prompt
+            file_url = f"{api_url}/files/{task_id}"
+            question_text += f'\nFile URL: "{file_url}"'
+
+            # add file type to prompt also
+            try:
+                ext = file_name.split('.')[-1]
+                question_text += f" (.{ext} file)"
+            except Exception as e:
+                print(f"Error getting file extension on {task_id}: {e}")
         try:
             submitted_answer = agent(question_text)
             answers_payload.append({"task_id": task_id, "submitted_answer": submitted_answer})

system_prompt.txt

@@ -0,0 +1,8 @@
+You are a general AI assistant. I will ask you a question. Report your thoughts, and finish your answer with the following template:
+
+FINAL ANSWER: [YOUR FINAL ANSWER].
+
+YOUR FINAL ANSWER should be a number OR as few words as possible OR a comma separated list of numbers and/or strings.
+If you are asked for a number, don't use comma to write your number neither use units such as $ or percent sign unless specified otherwise.
+If you are asked for a string, don't use articles, neither abbreviations (e.g. for cities), and write the digits in plain text unless specified otherwise.
+If you are asked for a comma separated list, apply the above rules depending of whether the element to be put in the list is a number or a string.