from langchain_ollama import Ollama
from langchain.agents import initialize_agent, AgentExecutor, AgentType
from langchain.tools import BaseTool
from typing import List

def create_agent(tools: List[BaseTool]) -> AgentExecutor:
    """
    Create a LangChain agent that can use the provided tools.

    Parameters:
        tools (List[BaseTool]): List of tools for the agent.

    Returns:
        AgentExecutor: Configured agent.
    """
    llm = Ollama(model="llama3")
    system_prompt = (
        "You are an AI assistant with access to a knowledge base. "
        "Use the following tools to answer user queries:\n"
        "- search_knowledge_base: Search the knowledge base.\n"
        "- add_to_knowledge_base: Add a new document to the knowledge base.\n"
        "When you need to use a tool, call it with the appropriate arguments."
    )
    agent = initialize_agent(
        tools=tools,
        llm=llm,
        agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
        verbose=True,
        agent_kwargs={"system_message": system_prompt},
    )
    return agent