Agente Text-to-SQL con LangGraph

from langchain_openai import ChatOpenAI
from langchain_core.tools import tool
from langgraph.prebuilt import create_react_agent
from langchain_community.utilities import SQLDatabase
from langchain_community.agent_toolkits import SQLDatabaseToolkit

db = SQLDatabase.from_uri("sqlite:///sales.db", sample_rows_in_table_info=3)
toolkit = SQLDatabaseToolkit(db=db, llm=model)
sql_tools = toolkit.get_tools()

agent = create_react_agent(
    ChatOpenAI(model="gpt-4o"),
    tools=[sql_tools],
    prompt="You are a SQL analyst. Convert natural language questions into SQL queries. Only use SELECT statements. Limit results to 10 rows.",
)

result = await agent.ainvoke({
    "messages": [("user", "Show me top 5 customers by total spending this quarter")]
})
print(result["messages"][-1].content)