SDK usage

The SDK has one function per request format. litellm.decisions takes the OpenAI Decisions shape (input, a questions list and an optional safety_identifier) and returns the OpenAI response, with answers as a list. litellm.systemone takes the System One shape (state and a questions mapping keyed by question name) and returns the System One response, with answers keyed by question name. Both work with every supported provider, so you pick the function by the request shape you write, not by the provider you call.

OpenAI Decisions format

import os
import litellm

os.environ["OPENAI_API_KEY"] = ""

response = litellm.decisions(
    model="openai/gpt-6-luna",
    input="Customer wrote: I was charged twice for my order #4411 and want one of the charges refunded today.",
    questions=[
        {"type": "predicate", "name": "is_refund_request", "instructions": "Is the customer asking for a refund?"},
    ],
)
print(response.answers[0].probability)
print(response.usage)

System One format

import os
import litellm

os.environ["TYPESAFE_API_KEY"] = ""

response = litellm.systemone(
    model="typesafe/jev-latest",
    state="Customer wrote: I was charged twice for my order #4411 and want one of the charges refunded today.",
    questions={
        "is_refund_request": {"type": "noul", "instructions": "Is the customer asking for a refund?"},
    },
)
print(response.answers["is_refund_request"].noul)

The async versions are litellm.adecisions and litellm.asystemone and take the same arguments.

import asyncio
import os
import litellm

os.environ["TYPESAFE_API_KEY"] = ""

async def main():
    response = await litellm.asystemone(
        model="typesafe/jev-latest",
        state="Customer wrote: I was charged twice for my order #4411 and want one of the charges refunded today.",
        questions={
            "is_refund_request": {"type": "noul", "instructions": "Is the customer asking for a refund?"},
        },
    )
    print(response.answers["is_refund_request"].noul)

asyncio.run(main())

All four functions also accept safety_identifier, api_key, api_base, timeout, custom_llm_provider and extra_headers. litellm.systemone and litellm.asystemone also take images, a list of image URLs or data URLs, and assets, the TypeSafe image map described in TypeSafe images, box questions and long context. Passing images to litellm.decisions raises a BadRequestError unless drop_params is on, since the OpenAI format carries images as input_image parts. Passing input to litellm.systemone raises a BadRequestError that points at litellm.decisions. Passing state to litellm.decisions still works for existing callers, it sends the System One format and emits a UserWarning that points at litellm.systemone. A model whose prefix is not one of the supported providers fails with a BadRequestError that lists the supported ones.

Through the Router the same split applies: router.decisions and router.adecisions take the OpenAI shape, router.systemone and router.asystemone take the System One shape. On the proxy, /v1/systemone requests are logged with call type asystemone and /v1/decisions requests with adecisions.

Upgrading from v1.104.x

In v1.104.2 through v1.104.x, litellm.decisions accepted both shapes and picked the format from whether you passed input or state. Those calls keep working unchanged, with a UserWarning. Rename litellm.decisions(state=...) to litellm.systemone(state=...) when convenient, the arguments stay the same.