agent.py

import os

from langchain_openai import ChatOpenAI
from langchain_community.tools import BraveSearch  # web search
from langchain.tools import Calculator  # for basic math
from langchain.tools.python.tool import PythonAstREPLTool  # for logic/math problems

# gpt-4.1-nano (cheaper for debugging) with temperature 0 for less randomness
# for benchmarking use gpt-4.1-mini or 04-mini

llm = ChatOpenAI(model="gpt-4.1-nano", temperature=0)

search_tool = BraveSearch.from_api_key(
                    api_key=os.getenv("BRAVE_SEARCH_API"),
                    search_kwargs={"count": 4},  # returns the 4 best results and their URL
                    description="Web search using Brave"
)