Update agent.py

agent.py

@@ -0,0 +1,146 @@
+import os
+import base64
+from langchain_core.messages import HumanMessage, SystemMessage
+from langchain_openai import ChatOpenAI
+from langchain_community.tools import DuckDuckGoSearchResults
+from langchain_community.utilities import DuckDuckGoSearchAPIWrapper
+import wikipediaapi
+import json
+import asyncio
+import aiohttp
+from langchain_core.tools import tool
+from langgraph.graph import START, StateGraph, MessagesState
+from langgraph.prebuilt import tools_condition
+from langgraph.prebuilt import ToolNode
+
+import requests
+
+system_prompt = """You are a helpful assistant tasked with answering questions using a set of tools.
+Now, 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.
+Your answer should only start with "FINAL ANSWER: ", then follows with the answer.
+"""
+
+api_key = os.getenv("OPENAI_API_KEY")
+
+model = ChatOpenAI(model="gpt-4o-mini", api_key=api_key, temperature=0)
+
+@tool
+def search_wiki(query: str, max_results: int = 3) -> str:
+    """
+    Searches Wikipedia for the given query and returns a maximum of 'max_results'
+    relevant article summaries, titles, and URLs.
+
+    Args:
+        query (str): The search query for Wikipedia.
+        max_results (int): The maximum number of search results to retrieve (default is 3).
+
+    Returns:
+        str: A JSON string containing a list of dictionaries, where each dictionary
+             represents a Wikipedia article with its title, summary, and URL.
+             Returns an empty list if no results are found or an error occurs.
+    """
+
+    language_code = 'en'
+
+    headers={'User-Agent': 'LangGraphAgent/1.0 (dwrigley@opensourceconnections.com)'}
+
+    base_url = 'https://api.wikimedia.org/core/v1/wikipedia/'
+    endpoint = '/search/page'
+    url = base_url + language_code + endpoint
+    parameters = {'q': query, 'limit': max_results}
+    response = requests.get(url, headers=headers, params=parameters)
+    response = json.loads(response.text)
+    return json.dumps(response, indent=2)
+
+
+@tool
+def search_web(query: str, max_results: int = 3) -> str:
+    """
+    Searches the web for the given query and returns a maximum of 'max_results'
+    relevant hits.
+
+    Args:
+        query (str): The search query for the web search.
+        max_results (int): The maximum number of search results to retrieve (default is 3).
+
+    Returns:
+        str: A JSON string containing a list, where each entry
+             represents a search result article with its snippet, title, link and other metadata.
+             Returns an empty list if no results are found or an error occurs.
+    """
+    try:
+        wrapper = DuckDuckGoSearchAPIWrapper(max_results=max_results)
+        search = DuckDuckGoSearchResults(api_wrapper=wrapper)
+        #search = DuckDuckGoSearchResults()
+        results = search.invoke(query)
+        return results
+    except Exception as e:
+        print(f"An error occurred during web search: {e}")
+        return json.dumps([]) # Return an empty JSON list on error
+
+tools = [
+    search_web,
+    search_wiki
+]
+
+def build_graph():
+    """Build the graph"""
+    # Bind tools to LLM
+    llm_with_tools = model.bind_tools(tools)
+
+    # Node
+    def assistant(state: MessagesState):
+        """Assistant node"""
+        return {"messages": [llm_with_tools.invoke(state["messages"])]}
+    
+    builder = StateGraph(MessagesState)
+    builder.add_node("assistant", assistant)
+    builder.add_node("tools", ToolNode(tools))
+    builder.add_edge(START, "assistant")
+    builder.add_conditional_edges(
+        "assistant",
+        tools_condition,
+    )
+    builder.add_edge("tools", "assistant")
+
+    # Compile graph
+    return builder.compile()
+
+# --- Testing the tools ---
+
+# Test case: Basic Wikipedia search
+print("--- Test Case 1: Basic Search ---")
+query1 = "Principle of double effect"
+result1 = search_wiki.invoke(query1)
+print(f"Query: '{query1}'")
+print(f"Result Type: {type(result1)}")
+print(f"Result (first 500 chars): {result1[:500]}...")
+print("\n")
+
+# Test case: Basic web search
+print("--- Test Case 1: Basic Search ---")
+query1 = "Principle of double effect"
+result1 = search_web.invoke(query1)
+print(f"Query: '{query1}'")
+print(f"Result Type: {type(result1)}")
+print(f"Result (first 500 chars): {result1[:500]}...")
+print("\n")
+
+# test agent
+if __name__ == "__main__":
+    question = "When was St. Thomas Aquinas born?"
+    # Build the graph
+    graph = build_graph()
+    # Run the graph
+    messages = [
+        SystemMessage(
+            content=system_prompt
+        ),
+        HumanMessage(
+            content=question
+        )]
+    messages = graph.invoke({"messages": messages})
+    for m in messages["messages"]:
+        m.pretty_print()