openapi: 3.1.0
info:
  title: Black Forest Labs FLUX API
  description: |
    Asynchronous image generation API from Black Forest Labs. Submit a
    generation request to a model-specific endpoint and poll
    `/v1/get_result` (or use the optional webhook callback) for the
    finished image. Includes the FLUX, FLUX.1, and FLUX.2 model families,
    Fill/Expand image editing tools, credit lookup, and fine-tune
    management.
  version: "1.0"
  contact:
    name: Black Forest Labs
    url: https://docs.bfl.ai
servers:
  - url: https://api.bfl.ai
    description: Global
  - url: https://api.us.bfl.ai
    description: United States region
  - url: https://api.eu.bfl.ai
    description: European region (GDPR)
security:
  - apiKey: []
tags:
  - name: Generation
    description: Image generation endpoints.
  - name: Editing
    description: Image editing tools (fill, expand, erase).
  - name: Utility
    description: Result polling, credits, fine-tune management.
paths:
  /v1/flux-pro-1.1:
    post:
      tags: [Generation]
      summary: FLUX 1.1 [pro] generation
      operationId: generateFluxPro11
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GenerationRequest'
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/flux-pro-1.1-ultra:
    post:
      tags: [Generation]
      summary: FLUX 1.1 [pro] Ultra generation
      operationId: generateFluxPro11Ultra
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GenerationRequest'
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/flux-dev:
    post:
      tags: [Generation]
      summary: FLUX.1 [dev] generation
      operationId: generateFluxDev
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GenerationRequest'
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/flux-2-pro:
    post:
      tags: [Generation]
      summary: FLUX.2 [PRO] generation
      operationId: generateFlux2Pro
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GenerationRequest'
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/flux-2-flex:
    post:
      tags: [Generation]
      summary: FLUX.2 [FLEX] generation
      operationId: generateFlux2Flex
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GenerationRequest'
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
  /v1/flux-2-max:
    post:
      tags: [Generation]
      summary: FLUX.2 [MAX] generation
      operationId: generateFlux2Max
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GenerationRequest'
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
  /v1/flux-pro-1.0-fill:
    post:
      tags: [Editing]
      summary: FLUX.1 Fill [pro] - inpaint with a mask
      operationId: generateFluxFill
      requestBody:
        required: true
        content:
          application/json:
            schema:
              allOf:
                - $ref: '#/components/schemas/GenerationRequest'
                - type: object
                  required: [image]
                  properties:
                    image:
                      type: string
                      description: Base64-encoded source image.
                    mask:
                      type: string
                      description: Base64-encoded mask image.
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
  /v1/flux-pro-1.0-expand:
    post:
      tags: [Editing]
      summary: FLUX.1 Expand [pro] - outpaint
      operationId: generateFluxExpand
      requestBody:
        required: true
        content:
          application/json:
            schema:
              allOf:
                - $ref: '#/components/schemas/GenerationRequest'
                - type: object
                  required: [image]
                  properties:
                    image:
                      type: string
                      description: Base64-encoded source image.
                    top:
                      type: integer
                    bottom:
                      type: integer
                    left:
                      type: integer
                    right:
                      type: integer
      responses:
        '200':
          $ref: '#/components/responses/AsyncResponse'
  /v1/get_result:
    get:
      tags: [Utility]
      summary: Retrieve generation result
      operationId: getResult
      parameters:
        - in: query
          name: id
          required: true
          schema:
            type: string
          description: Task identifier returned by a generation endpoint.
      responses:
        '200':
          description: Current status (and result when ready).
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ResultResponse'
        '422':
          $ref: '#/components/responses/ValidationError'
  /v1/credits:
    get:
      tags: [Utility]
      summary: Get account credit balance
      operationId: getCredits
      responses:
        '200':
          description: Available credits.
          content:
            application/json:
              schema:
                type: object
                properties:
                  credits:
                    type: number
  /v1/my_finetunes:
    get:
      tags: [Utility]
      summary: List the caller's fine-tunes
      operationId: listFinetunes
      responses:
        '200':
          description: Fine-tune list.
  /v1/finetune_details:
    get:
      tags: [Utility]
      summary: Get fine-tune details
      operationId: getFinetuneDetails
      parameters:
        - in: query
          name: finetune_id
          required: true
          schema:
            type: string
      responses:
        '200':
          description: Fine-tune details.
  /v1/delete_finetune:
    post:
      tags: [Utility]
      summary: Delete a fine-tune
      operationId: deleteFinetune
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required: [finetune_id]
              properties:
                finetune_id:
                  type: string
      responses:
        '200':
          description: Deletion acknowledged.
components:
  securitySchemes:
    apiKey:
      type: apiKey
      in: header
      name: x-key
      description: BFL API key.
  responses:
    AsyncResponse:
      description: Generation task queued.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/AsyncResponse'
    ValidationError:
      description: Request validation failed.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/HTTPValidationError'
  schemas:
    GenerationRequest:
      type: object
      properties:
        prompt:
          type: string
        width:
          type: integer
        height:
          type: integer
        aspect_ratio:
          type: string
          example: "16:9"
        seed:
          type: integer
        prompt_upsampling:
          type: boolean
          default: false
        safety_tolerance:
          type: integer
          minimum: 0
          maximum: 6
        output_format:
          type: string
          enum: [jpeg, png, webp]
        webhook_url:
          type: string
          format: uri
        webhook_secret:
          type: string
    AsyncResponse:
      type: object
      properties:
        id:
          type: string
        polling_url:
          type: string
          format: uri
    ResultResponse:
      type: object
      properties:
        id:
          type: string
        status:
          type: string
          enum: [Pending, Ready, Error, "Task not found", "Request Moderated", "Content Moderated"]
        result:
          type: object
          nullable: true
          properties:
            sample:
              type: string
              format: uri
        progress:
          type: number
          nullable: true
        details:
          type: object
          nullable: true
        preview:
          type: object
          nullable: true
    HTTPValidationError:
      type: object
      properties:
        detail:
          type: array
          items:
            type: object
            properties:
              loc:
                type: array
                items:
                  oneOf:
                    - type: string
                    - type: integer
              msg:
                type: string
              type:
                type: string