Having a very hard time getting structured outputs to work

General
,
2

Which LLM are you using? It’s working for me on every run (I’ve tested it with both Gemini and OpenAI):

from crewai import Agent, LLM
from pydantic import BaseModel, Field
from typing import Optional, List, Annotated
import asyncio
import os

os.environ["OPENAI_API_KEY"] = "<your-key>"

async def get_founders_names():
    class FounderNames(BaseModel):
        names: Optional[Annotated[
            List[str],
            Field(description="List of the full names of the company founders")
        ]] = None
    
    llm = LLM(
        model="gpt-4o",
        temperature=0.5
    )
    
    researcher_agent = Agent(
        role="Data Extraction Research Specialist",
        goal=(
            "Extract relevant information from sources and structure it into "
            "clean, organized data formats"
        ),
        backstory=(
            "You are a detail-oriented researcher who specializes in finding "
            "key information and organizing it into clear, structured outputs."
        ),
        llm=llm,
        allow_delegation=False,
        verbose=True
    )

    query = (
        "Extract the names of the founders of Dunder Mifflin company from the "
        "text below:\n\n"
        "Willy Wonka founded the Wonka Chocolate Factory. Dunder Mifflin (The "
        "Office) was founded in 1949 by Robert Dunder and Robert Mifflin. Elon "
        "Musk founded SpaceX in 2002."
    )

    result = await researcher_agent.kickoff_async(
        query, response_format=FounderNames
    )

    print("\nresult:\n")
    print(f"{result.pydantic=}")
    print(f"{type(result.pydantic)=}\n")

async def main():
    await get_founders_names()

if __name__ == "__main__":
    asyncio.run(main())