---
title: "POST /v1/systemone"
method: POST
path: "/v1/systemone"
tags: ["inference"]
---

# POST /v1/systemone

`POST /v1/systemone`

## Request

- The document declares no server URL.
- Auth: one of:
  - HTTP bearer
  - API key in header `x-api-key`

System One-compatible typed decisions over SIE's native extract primitive. Answers one state (a string, an object, or a list of conversation turns) against typed noul, choice and score questions with a decision model. Clients written for the System One API work by changing their base URL. A state or question set that does not fit the model's window is refused with 422.

## Headers

- `X-SIE-MACHINE-PROFILE` string, nullable
- `X-SIE-Pool` string, nullable
- `X-SIE-SDK-Version` string, nullable

## Request body

- SystemOneRequest: A System One request: one state and its typed questions. Fields the route does not read are ignored.
  - `model` string, required: SIE model id of a decision model, e.g. `fastino/GLiNER2.5-Decide`.
  - `questions` object, required: Typed questions by id: `{"type": "noul" | "choice" | "score", "instructions"?, "criteria"?}`. A score question takes 1 to 10 levels.
  - `state` unknown, required

## Response `200`

Every question answered

- SystemOneResponse: Answers by question id, in the System One response shape.
  - `answers` object, required: One answer per question: `noul` (`noul`, the probability of yes, `answer` and `confidence`), `choice` (`choice`, `confidence`, `probabilities` by option) or `score` (`score`, `confidence`, `legend` and `probabilities` by level index).
  - `model` string, required
  - `usage` SystemOneUsage, required: Tokens the decision model read; it generates none.
    - `input_tokens` integer, required
    - `output_tokens` integer, required

## Other responses

- `401`: Missing or invalid bearer token
- `404`: Model not found
- `413`: Request body too large
- `422`: Invalid request, a model that does not answer typed questions, or input that does not fit the model's window
- `500`: Malformed native extract result; gateway auth enabled but no tokens configured
- `502`: MODEL_LOAD_FAILED
- `503`: Provisioning, model loading, or capacity exhausted; Retry-After at most 60 seconds

## Changes

- **2026-10-16** `b33f92ccc3a4`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/superlinked/apis/sie-gateway/changes/v1/systemone/post.md)

---

[API](https://skmtc.dev/superlinked/apis/sie-gateway.md) - [All operations](https://skmtc.dev/superlinked/apis/sie-gateway/llms.txt) - [OpenAPI document](https://skmtc.dev/superlinked/apis/sie-gateway/revisions/796338a4d23c?raw)