Hyperbolic Image Generation API

openapi: 3.1.0
info:
  title: Hyperbolic Image Generation API
  description: >
    Generate images from text prompts using diffusion models hosted by
    Hyperbolic — Stable Diffusion XL, Stable Diffusion 3.5, FLUX.1 [schnell]
    and FLUX.1 [dev] (sunset), and ControlNet variants. Custom LoRA support.
    Pricing starts at $0.0025 per image.
  version: v1
  contact:
    name: Hyperbolic Support
    email: support@hyperbolic.ai
    url: https://docs.hyperbolic.ai
  license:
    name: Hyperbolic Terms of Use
    url: https://www.hyperbolic.ai/terms-of-use

servers:
  - url: https://api.hyperbolic.xyz/v1
    description: Hyperbolic Production Inference Server

security:
  - BearerAuth: []

tags:
  - name: Image Generation
    description: Text-to-image diffusion endpoint

paths:
  /image/generation:
    post:
      summary: Hyperbolic Generate An Image
      description: >
        Generate one or more images from a text prompt using the specified
        diffusion model. Returns base64-encoded images in the `images` array.
      operationId: generateImage
      tags:
        - Image Generation
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ImageGenerationRequest'
            examples:
              SDXLBasic:
                summary: Basic SDXL generation
                value:
                  model_name: SDXL1.0-base
                  prompt: A photorealistic cyberpunk cat wearing sunglasses
                  steps: 30
                  cfg_scale: 7.5
                  height: 1024
                  width: 1024
      responses:
        '200':
          description: Successful image generation
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ImageGenerationResponse'
        '400':
          description: Bad Request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '429':
          description: Too Many Requests
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

components:
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API Key

  schemas:
    ImageGenerationRequest:
      type: object
      required:
        - model_name
        - prompt
      properties:
        model_name:
          type: string
          description: >
            Image model identifier — e.g. `SDXL1.0-base`, `SD3.5`,
            `FLUX.1-dev` (sunset), `FLUX.1-schnell` (sunset),
            `ControlNet-SDXL`.
        prompt:
          type: string
        negative_prompt:
          type: string
        steps:
          type: integer
          minimum: 1
          maximum: 100
          default: 30
        cfg_scale:
          type: number
          minimum: 1
          maximum: 20
          default: 7.5
        height:
          type: integer
          minimum: 64
          maximum: 2048
          default: 1024
        width:
          type: integer
          minimum: 64
          maximum: 2048
          default: 1024
        seed:
          type: integer
        n:
          type: integer
          minimum: 1
          maximum: 4
          default: 1
        lora:
          type: object
          description: Custom LoRA configuration when supported by the model.

    ImageGenerationResponse:
      type: object
      properties:
        images:
          type: array
          items:
            type: object
            properties:
              image:
                type: string
                description: Base64-encoded image bytes.
              seed:
                type: integer
        inference_time:
          type: number
          description: Seconds spent in inference.

    ErrorResponse:
      type: object
      properties:
        error:
          type: object
          properties:
            message:
              type: string
            type:
              type: string
            code:
              type: string