result_type as List

[fils]

I don't know if this is related to #242 or not.

I am trying to replicate this from the Ollama examples (ref: https://ollama.com/blog/structured-outputs)

from openai import OpenAI
import openai
from pydantic import BaseModel

client = OpenAI(base_url="http://192.168.202.137:11434/v1", api_key="ollama")

class Pet(BaseModel):
    name: str
    animal: str
    age: int
    color: str | None
    favorite_toy: str | None

class PetList(BaseModel):
    pets: list[Pet]

try:
    completion = client.beta.chat.completions.parse(
        temperature=0,
        model='llama3.2:3b',
        messages=[
            {"role": "user", "content": '''
                I have two pets.
                A cat named Luna who is 5 years old and loves playing with yarn. She has grey fur.
                I also have a 2 year old black cat named Loki who loves tennis balls.
            '''}
        ],
        response_format=PetList,
    )

    pet_response = completion.choices[0].message
    if pet_response.parsed:
        print(pet_response.parsed)
    elif pet_response.refusal:
        print(pet_response.refusal)
except Exception as e:
    if type(e) == openai.LengthFinishReasonError:
        print("Too many tokens: ", e)
        pass
    else:
        print(e)
        pass

In pydantic-al I try

from pydantic import BaseModel
from pydantic_ai import Agent
from pydantic_ai.models.ollama import OllamaModel

ollama_model = OllamaModel(
    model_name='llama3.2:3b',
    base_url='http://192.168.202.137:11434/v1'
)

class Pet(BaseModel):
  name: str
  animal: str
  age: int
  color: str | None
  favorite_toy: str | None

class PetList(BaseModel):
  pets: list[Pet]


# # Create a system prompt to guide the model
SYSTEM_PROMPT = """
You are a helper that extracts pet information from text and formats it as a list.
For each pet mentioned, extract:
- name
- animal type
- age
- color (if mentioned)
- favorite toy (if mentioned)

Format as a JSON object with a 'pets' array containing each pet's details.
"""

agent3 = Agent(model=ollama_model, result_type=PetList, retries=3)
result3 = agent3.run_sync(('I have two pets. A cat named Luna who is 5 years old'
                           ' and loves playing with yarn. She has grey fur. I also '
                           'have a 2 year old black cat named Loki who loves tennis balls.'))
pet_data = result3.data
print(pet_data)

passing PetList to the result_type. This will fail.

If I just pass Pet, ie, result_type=Pet it will sometimes work, getting only 1 cat of course, but also fail sometimes.

Any guidance on how to address this would be appreciated.