feat: add System One API support

README.md

@@ -255,6 +255,47 @@ ollama.embed(model='gemma4', input=['The sky is blue because of rayleigh scatter
 ollama.ps()
 ```
 
+### System One
+
+```python
+import ollama
+
+response = ollama.systemone(
+  model='nimble',
+  state='Our checkout has returned 500 errors since 9am.',
+  questions={
+    'team': {
+      'type': 'choice',
+      'instructions': 'Which team should handle this ticket?',
+      'criteria': {'billing': 'Payments and refunds', 'technical': 'Software errors'},
+    },
+  },
+)
+print(response.answers['team'])
+```
+
+System One uses `POST /v1/systemone` and requires Ollama v0.35.0 or later with a
+compatible local model such as `nimble`. It returns one JSON response; streaming
+and cloud models are not supported.
+
+`state` and question `instructions` accept text, JSON objects, or arrays. Questions
+are evaluated in their supplied order:
+
+- `choice`: 2–26 option keys mapped to descriptions; `None` uses the key as its description.
+- `noul`: probability of true, with optional `{"false": "No", "true": "Yes"}` descriptions.
+- `score`: 2–26 descriptions ordered lowest to highest; returns a potentially fractional, zero-based score.
+
+Responses contain `model`, `answers`, and `usage.input_tokens` / `usage.output_tokens`.
+Confidence measures probability concentration, not calibrated correctness.
+Token usage comes from the server; output tokens are not necessarily zero.
+Optional `keep_alive` accepts seconds or a duration string. Requests use the client's
+existing host, headers, and HTTP error handling. The server validates its body and
+model context limits without truncating input.
+
+Available as `ollama.systemone`, `Client.systemone`, and `await AsyncClient.systemone`.
+Question and answer types, including `SystemOneResponse`, are exported from `ollama`.
+See [the combined question example](examples/systemone.py).
+
 ## Errors
 
 Errors are raised if requests return an error status or if an error is detected while streaming.

examples/README.md

@@ -127,3 +127,7 @@ Requirement: `pip install tqdm`
 ### Thinking (levels) - Choose the thinking level
 
 - [thinking-levels.py](thinking-levels.py)
+
+### System One - Score typed questions
+
+- [systemone.py](systemone.py) - Choice, boolean probability, and rubric score questions

examples/systemone.py

@@ -0,0 +1,13 @@
+import ollama
+
+# Requires Ollama v0.35.0 or later and the local nimble model.
+response = ollama.systemone(
+  model='nimble',
+  state={'ticket': 'I was charged twice. Please refund the extra payment.'},
+  questions={
+    'team': {'type': 'choice', 'instructions': 'Which team should handle this ticket?', 'criteria': {'billing': 'Payments and refunds', 'technical': 'Bugs and integrations', 'other': 'None of the above'}},
+    'refund': {'type': 'noul', 'instructions': 'Does the customer explicitly ask for a refund?'},
+    'urgency': {'type': 'score', 'instructions': 'How urgent is this ticket?', 'criteria': ['Routine', 'Soon', 'Urgent']},
+  },
+)
+print(response.model_dump())

ollama/__init__.py

@@ -14,6 +14,18 @@
   ResponseError,
   ShowResponse,
   StatusResponse,
+  SystemOneAnswer,
+  SystemOneChoiceAnswer,
+  SystemOneChoiceQuestion,
+  SystemOneContent,
+  SystemOneNoulAnswer,
+  SystemOneNoulQuestion,
+  SystemOneQuestion,
+  SystemOneRequest,
+  SystemOneResponse,
+  SystemOneScoreAnswer,
+  SystemOneScoreQuestion,
+  SystemOneUsage,
   Tool,
   WebFetchResponse,
   WebSearchResponse,
@@ -36,6 +48,18 @@
   'ResponseError',
   'ShowResponse',
   'StatusResponse',
+  'SystemOneAnswer',
+  'SystemOneChoiceAnswer',
+  'SystemOneChoiceQuestion',
+  'SystemOneContent',
+  'SystemOneNoulAnswer',
+  'SystemOneNoulQuestion',
+  'SystemOneQuestion',
+  'SystemOneRequest',
+  'SystemOneResponse',
+  'SystemOneScoreAnswer',
+  'SystemOneScoreQuestion',
+  'SystemOneUsage',
   'Tool',
   'WebFetchResponse',
   'WebSearchResponse',
@@ -57,3 +81,4 @@
 ps = _client.ps
 web_search = _client.web_search
 web_fetch = _client.web_fetch
+systemone = _client.systemone

ollama/_client.py

@@ -66,6 +66,10 @@
   ShowRequest,
   ShowResponse,
   StatusResponse,
+  SystemOneContent,
+  SystemOneQuestion,
+  SystemOneRequest,
+  SystemOneResponse,
   Tool,
   WebFetchRequest,
   WebFetchResponse,
@@ -403,6 +407,29 @@ def add_two_numbers(a: int, b: int) -> int:
       stream=stream,
     )
 
+  def systemone(
+    self,
+    model: str,
+    state: SystemOneContent,
+    questions: Mapping[str, Union[SystemOneQuestion, Mapping[str, Any]]],
+    keep_alive: Optional[Union[float, str]] = None,
+  ) -> SystemOneResponse:
+    """Score choice, noul, and score questions with a local System One model.
+
+    Returns one JSON response. Streaming is not supported.
+    """
+    return self._request(
+      SystemOneResponse,
+      'POST',
+      '/v1/systemone',
+      json=SystemOneRequest(
+        model=model,
+        state=state,
+        questions=questions,
+        keep_alive=keep_alive,
+      ).model_dump(exclude_none=True),
+    )
+
   def embed(
     self,
     model: str = '',
@@ -1036,6 +1063,29 @@ def add_two_numbers(a: int, b: int) -> int:
       stream=stream,
     )
 
+  async def systemone(
+    self,
+    model: str,
+    state: SystemOneContent,
+    questions: Mapping[str, Union[SystemOneQuestion, Mapping[str, Any]]],
+    keep_alive: Optional[Union[float, str]] = None,
+  ) -> SystemOneResponse:
+    """Score choice, noul, and score questions with a local System One model.
+
+    Returns one JSON response. Streaming is not supported.
+    """
+    return await self._request(
+      SystemOneResponse,
+      'POST',
+      '/v1/systemone',
+      json=SystemOneRequest(
+        model=model,
+        state=state,
+        questions=questions,
+        keep_alive=keep_alive,
+      ).model_dump(exclude_none=True),
+    )
+
   async def embed(
     self,
     model: str = '',

ollama/_types.py

@@ -618,6 +618,76 @@ class WebFetchResponse(SubscriptableBaseModel):
   links: Optional[Sequence[str]] = None
 
 
+SystemOneContent = Union[str, Dict[str, Any], List[Any]]
+"""Text or JSON object/array rendered as text by System One."""
+
+
+class SystemOneChoiceQuestion(SubscriptableBaseModel):
+  type: Literal['choice'] = 'choice'
+  instructions: SystemOneContent
+  criteria: Dict[str, Optional[str]]
+  'Ordered choices; a null description uses the choice key.'
+
+
+class SystemOneNoulQuestion(SubscriptableBaseModel):
+  type: Literal['noul'] = 'noul'
+  instructions: SystemOneContent
+  criteria: Optional[Dict[Literal['false', 'true'], str]] = None
+
+
+class SystemOneScoreQuestion(SubscriptableBaseModel):
+  type: Literal['score'] = 'score'
+  instructions: SystemOneContent
+  criteria: List[str]
+  'Descriptions ordered from lowest to highest score.'
+
+
+SystemOneQuestion = Annotated[Union[SystemOneChoiceQuestion, SystemOneNoulQuestion, SystemOneScoreQuestion], Field(discriminator='type')]
+
+
+class SystemOneRequest(SubscriptableBaseModel):
+  model: str
+  state: SystemOneContent
+  questions: Dict[str, SystemOneQuestion]
+  keep_alive: Optional[Union[float, str]] = None
+
+
+class SystemOneNoulAnswer(SubscriptableBaseModel):
+  type: Literal['noul']
+  noul: float
+  'Probability of true.'
+
+
+class SystemOneChoiceAnswer(SubscriptableBaseModel):
+  type: Literal['choice']
+  choice: str
+  probabilities: Dict[str, float]
+  confidence: float
+
+
+class SystemOneScoreAnswer(SubscriptableBaseModel):
+  type: Literal['score']
+  score: float
+  'Expected zero-based score, which may be fractional.'
+  legend: Dict[str, str]
+  probabilities: Dict[str, float]
+  confidence: float
+
+
+SystemOneAnswer = Annotated[Union[SystemOneNoulAnswer, SystemOneChoiceAnswer, SystemOneScoreAnswer], Field(discriminator='type')]
+
+
+class SystemOneUsage(SubscriptableBaseModel):
+  input_tokens: int
+  output_tokens: int
+
+
+class SystemOneResponse(SubscriptableBaseModel):
+  model: str
+  answers: Dict[str, SystemOneAnswer]
+  usage: SystemOneUsage
+
+
 class RequestError(Exception):
   """
   Common class for request errors.

tests/test_systemone.py

@@ -0,0 +1,88 @@
+import inspect
+import json
+
+import httpx
+import pytest
+
+import ollama
+
+
+@pytest.fixture
+def anyio_backend():
+  return 'asyncio'
+
+
+@pytest.mark.anyio
+@pytest.mark.parametrize('variant', ['sync', 'async', 'module'])
+async def test_systemone_wire_and_answers(variant, monkeypatch):
+  questions = {
+    'team': {'type': 'choice', 'instructions': {'task': 'Route ticket'}, 'criteria': {'technical': None, 'billing': 'Payments'}},
+    'refund': ollama.SystemOneNoulQuestion(instructions=['Refund requested?']),
+    'urgency': {'type': 'score', 'instructions': 'Urgency?', 'criteria': ['Routine', 'Urgent']},
+  }
+  expected = {
+    'model': 'nimble',
+    'state': {'ticket': ['Duplicate charge', None], 'paid': True},
+    'questions': {
+      'team': {'type': 'choice', 'instructions': {'task': 'Route ticket'}, 'criteria': {'technical': None, 'billing': 'Payments'}},
+      'refund': {'type': 'noul', 'instructions': ['Refund requested?']},
+      'urgency': {'type': 'score', 'instructions': 'Urgency?', 'criteria': ['Routine', 'Urgent']},
+    },
+  }
+  # Exercise both omission and numeric zero without duplicating the client matrix.
+  if variant == 'sync':
+    expected['keep_alive'] = 0
+  elif variant == 'async':
+    expected['keep_alive'] = '5m'
+  result = {
+    'model': 'nimble',
+    'answers': {
+      'team': {'type': 'choice', 'choice': 'billing', 'probabilities': {'technical': 0.2, 'billing': 0.8}, 'confidence': 0.3},
+      'refund': {'type': 'noul', 'noul': 0.9},
+      'urgency': {'type': 'score', 'score': 0.25, 'legend': {'0': 'Routine', '1': 'Urgent'}, 'probabilities': {'0': 0.75, '1': 0.25}, 'confidence': 0.2},
+    },
+    'usage': {'input_tokens': 123, 'output_tokens': 4},
+  }
+
+  def handle(request):
+    assert request.method == 'POST'
+    assert str(request.url) == 'http://sdk.test:11474/v1/systemone'
+    assert request.headers['authorization'] == 'Bearer synthetic'
+    body = json.loads(request.content)
+    assert body == expected
+    assert list(body['questions']) == ['team', 'refund', 'urgency']
+    assert list(body['questions']['team']['criteria']) == ['technical', 'billing']
+    return httpx.Response(200, json=result)
+
+  transport = httpx.MockTransport(handle)
+  if variant == 'module':
+    monkeypatch.setattr(ollama._client, '_client', httpx.Client(base_url='http://sdk.test:11474', headers={'authorization': 'Bearer synthetic'}, transport=transport))
+    method = ollama.systemone
+  else:
+    client = (ollama.AsyncClient if variant == 'async' else ollama.Client)(host='http://sdk.test:11474', headers={'authorization': 'Bearer synthetic'}, transport=transport)
+    method = client.systemone
+  kwargs = {key: expected[key] for key in ('model', 'state', 'keep_alive') if key in expected}
+  response = method(**kwargs, questions=questions)
+  if inspect.isawaitable(response):
+    response = await response
+  assert response.model_dump() == result
+  assert isinstance(response.answers['team'], ollama.SystemOneChoiceAnswer)
+  assert isinstance(response.answers['refund'], ollama.SystemOneNoulAnswer)
+  assert isinstance(response.answers['urgency'], ollama.SystemOneScoreAnswer)
+  assert response['answers']['urgency']['score'] == 0.25
+
+
+@pytest.mark.anyio
+@pytest.mark.parametrize('client_type', [ollama.Client, ollama.AsyncClient])
+@pytest.mark.parametrize('status,message', [(400, 'state must not be empty'), (404, "model 'missing' not found"), (413, 'request body must not exceed 64 KiB'), (503, 'server busy')])
+async def test_systemone_http_errors(client_type, status, message):
+  def handle(request):
+    return httpx.Response(status, json={'error': message})
+
+  client = client_type(transport=httpx.MockTransport(handle))
+  with pytest.raises(ollama.ResponseError) as error:
+    response = client.systemone('nimble', 'ticket', {'refund': {'type': 'noul', 'instructions': 'Refund?'}})
+    if inspect.isawaitable(response):
+      await response
+  assert error.value.status_code == status
+  assert error.value.error == message