System One Adapter

A drop-in replacement for typesafe_sdk's system_one evaluation API, backed by LLM APIs instead of TypeSafe.

Useful for comparing TypeSafe against an LLM on cost/speed/intelligence.

Install

The provider SDKs are optional extras — install the one(s) you use:

pip install 'system-one-adapter[openai]'      # OpenAI-compatible providers
pip install 'system-one-adapter[anthropic]'   # native Anthropic

Usage

Unlike TypeSafeClient, the client is configured with how the LLM should answer, and each call names a provider alongside the model:

from system_one_adapter import SystemOneAdapterClient, Noul, Score, Choice

client = SystemOneAdapterClient(
    structured_outputs=True,  # use the provider's native structured-output mode
    llm_answer_mode="probabilities",  # or "discrete"
    normalize_probabilities=True,
)

response = client.system_one(
    state="This book was a delight to read.",
    questions={"positive": Noul(instructions="The book review is positive.")},
    provider="openai",  # "openai" or "anthropic"
    model="gpt-4o-mini",
)

provider and model may also be set on the constructor as defaults. provider is required unless model is a Provider instance (e.g. a custom OpenAI-compatible endpoint):

from system_one_adapter.providers import OpenAIProvider

client.system_one(state, questions, model=OpenAIProvider("grok-4", base_url="https://api.x.ai/v1"))

Response

The response is a typesafe_sdk.SystemOneResponse subclass — same answers and typed views — with two additions:

• response.usage adds input_tokens_total / output_tokens_total (across retries), n_retries, n_retries_malformed_structure, and latency.
• response.debug holds retry_reasons and probability-normalization diagnostics.

It is a msgspec.Struct like every SDK response, so serialize it the same way (there is no model_dump):

import msgspec

print(msgspec.json.encode(response).decode())

Async

AsyncSystemOneAdapterClient mirrors the sync client with await client.system_one(...) and async with.

Options