Anvil PDF Generation API

openapi: 3.0.3
info:
  title: Anvil PDF Generation API
  description: >-
    Generate new PDFs dynamically from HTML/CSS, structured Markdown, or
    Anvil's JSON-based layout definition. POST your content to
    /api/v1/generate-pdf and receive a binary PDF stream in return.
  version: 1.0.0
  contact:
    name: Anvil Support
    url: https://www.useanvil.com/docs/
  license:
    name: Proprietary
    url: https://www.useanvil.com/terms/
servers:
  - url: https://app.useanvil.com
    description: Anvil production server

security:
  - basicAuth: []

paths:
  /api/v1/generate-pdf:
    post:
      operationId: generatePdf
      summary: Generate a PDF from HTML or Markdown
      description: >-
        Generate a new PDF from HTML/CSS content or structured Markdown. Accepts
        a JSON payload describing the content type and data. Returns binary PDF
        bytes on success. For payloads exceeding 1 MB, use multipart/form-data.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/GeneratePdfRequest'
            examples:
              htmlExample:
                summary: HTML/CSS to PDF
                value:
                  type: html
                  title: Invoice
                  data:
                    html: '<h1>Hello World</h1><p>This is my PDF.</p>'
                    css: 'h1 { color: #333; }'
              markdownExample:
                summary: Markdown to PDF
                value:
                  type: markdown
                  title: Report
                  fontSize: 12
                  textColor: '#333333'
                  data:
                    - label: Introduction
                      content: This is the introduction section.
                    - label: Summary
                      content: This is the summary section.
          multipart/form-data:
            schema:
              $ref: '#/components/schemas/GeneratePdfRequest'
      responses:
        '200':
          description: Binary PDF bytes of the generated document.
          content:
            application/pdf:
              schema:
                type: string
                format: binary
        '400':
          description: Validation error in the request.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Missing or invalid API key.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '429':
          description: Rate limit exceeded.
          headers:
            Retry-After:
              description: Seconds to wait before retrying.
              schema:
                type: integer
            X-RateLimit-Limit:
              schema:
                type: integer
            X-RateLimit-Remaining:
              schema:
                type: integer
            X-RateLimit-Reset:
              schema:
                type: integer
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

components:
  securitySchemes:
    basicAuth:
      type: http
      scheme: basic
      description: >-
        HTTP Basic Auth using your Anvil API key as the username and an empty
        string as the password.

  schemas:
    GeneratePdfRequest:
      type: object
      required:
        - data
      properties:
        type:
          type: string
          description: >-
            Content type of the data payload. Use "html" for HTML/CSS content
            or "markdown" for structured Markdown sections.
          enum:
            - html
            - markdown
          default: markdown
        title:
          type: string
          description: Title to encode into the PDF document metadata.
        data:
          description: >-
            Content to render as a PDF. Format depends on the "type" field.
          oneOf:
            - $ref: '#/components/schemas/HtmlPdfData'
            - type: array
              items:
                $ref: '#/components/schemas/MarkdownPdfSection'
        page:
          $ref: '#/components/schemas/PageSettings'
        fontSize:
          type: number
          description: >-
            Font size for Markdown rendering (points). Applies only when
            type is "markdown".
          minimum: 5
          maximum: 30
        textColor:
          type: string
          description: >-
            Hex color code for text. Applies only when type is "markdown".
          pattern: '^#[0-9A-Fa-f]{6}$'
          example: '#333333'
        fontFamily:
          type: string
          description: >-
            Font family for text rendering. Applies only when type is "markdown".
        includeTimestamp:
          type: boolean
          description: >-
            When true, includes a timestamp in the generated PDF. Applies only
            when type is "markdown".
          default: true
        logo:
          $ref: '#/components/schemas/LogoSettings'

    HtmlPdfData:
      type: object
      description: HTML/CSS content for PDF generation.
      properties:
        html:
          type: string
          description: HTML markup string to render as a PDF.
        css:
          type: string
          description: CSS stylesheet string to apply to the HTML content.

    MarkdownPdfSection:
      type: object
      description: A single section of structured Markdown content.
      properties:
        label:
          type: string
          description: Section heading or label.
        content:
          type: string
          description: Markdown-formatted text content for this section.
        table:
          type: object
          description: Optional table data to include in this section.
          additionalProperties: true

    PageSettings:
      type: object
      description: Page size and margin settings.
      properties:
        width:
          type: string
          description: Page width (e.g., "8.5in", "216mm").
        height:
          type: string
          description: Page height (e.g., "11in", "279mm").
        marginTop:
          type: string
          description: Top margin (e.g., "1in", "25.4mm").
        marginBottom:
          type: string
          description: Bottom margin.
        marginLeft:
          type: string
          description: Left margin.
        marginRight:
          type: string
          description: Right margin.

    LogoSettings:
      type: object
      description: Logo configuration for Markdown-generated PDFs.
      properties:
        src:
          type: string
          format: uri
          description: URL of the logo image.
        width:
          type: string
          description: Logo display width.
        height:
          type: string
          description: Logo display height.

    ErrorResponse:
      type: object
      properties:
        name:
          type: string
          description: Error type name.
          example: ValidationError
        message:
          type: string
          description: Human-readable error message.
        fields:
          type: array
          description: Field-level validation errors.
          items:
            type: object
            properties:
              message:
                type: string
              property:
                type: string