Upstage

Upstage System One API

The System One API from Upstage — 1 operation(s) for system one.

Documentation GitHub OpenAPI

Operations 1

POST /systemone Decide Typed Questions About A State #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Upstage API (Solar Decide) System One API
  version: '2026-10-12'
  description: 'GENERATED FROM DOCUMENTATION by API Evangelist on 2026-10-12: 1 operation read from the public System One API reference page.'
  x-generated-from: documentation
  x-provenance: generated
  x-apievangelist-provenance: generated-from-docs
  x-authored-by: API Evangelist
  x-generated: '2026-10-12'
  x-generator: hand-authored from docs (subagent)
  x-sources:
  - https://console.upstage.ai/api/systemone
  - https://console.upstage.ai/api/systemone.md
servers:
- url: https://api.upstage.ai/v1
security:
- bearerAuth: []
tags:
- name: System One
paths:
  /systemone:
    post:
      operationId: createSystemOneDecision
      summary: Decide Typed Questions About A State
      tags:
      - System One
      x-source: https://console.upstage.ai/api/systemone
      description: Send a state with one or more typed questions; Solar Decide returns a choice, score or noul (yes/no probability) answer per question. Output tokens are not billed.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SystemOneRequest'
      responses:
        '200':
          description: Answers keyed by question name
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SystemOneResponse'
        '422':
          description: Validation failed (e.g. a choice question with more than 26 options)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    Question:
      type: object
      required:
      - type
      properties:
        type:
          type: string
          enum:
          - choice
          - score
          - noul
        instructions:
          type: string
        criteria:
          description: 'choice: object of option name to description (2 to 26 options); score: ordered array of level descriptions; omitted for noul.'
          oneOf:
          - type: object
            additionalProperties:
              type: string
          - type: array
            items:
              type: string
    Answer:
      type: object
      properties:
        type:
          type: string
          enum:
          - choice
          - score
          - noul
        choice:
          type: string
        score:
          type: number
        legend:
          type: object
          additionalProperties:
            type: string
        noul:
          type: number
          minimum: 0
          maximum: 1
        probabilities:
          type: object
          additionalProperties:
            type: number
        confidence:
          type: number
    Error:
      type: object
      properties:
        error:
          type: object
          properties:
            type:
              type: string
            message:
              type: string
    SystemOneResponse:
      type: object
      properties:
        model:
          type: string
        answers:
          type: object
          additionalProperties:
            $ref: '#/components/schemas/Answer'
        usage:
          type: object
          properties:
            input_tokens:
              type: integer
            output_tokens:
              type: integer
    SystemOneRequest:
      type: object
      required:
      - model
      - state
      - questions
      properties:
        model:
          type: string
          examples:
          - solar-decide
        state:
          type: string
          description: The state to decide about (documented example uses a string).
        questions:
          type: object
          additionalProperties:
            $ref: '#/components/schemas/Question'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer