fourzerotwo-si Web API

openapi: 3.2.0
info:
  title: Fourzerotwo Si Web API
  version: 1.1.0
  contact:
    url: https://fourzerotwo.si
  description: 'Operations tagged web across 2 of this provider''s published API definitions: openapi.json, fourzerotwo-si-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://fourzerotwo.si
tags:
- name: Web
  description: 'Web Reader: Read any public web page as clean markdown, get its link-preview metadata, or check a URL for warning signs before opening it.'
paths:
  /v1/web/read:
    get:
      operationId: web__read
      summary: 'Web Reader: Read a page as markdown'
      description: 'Main content of a public web page as clean markdown, with title, byline, published date, canonical URL, language, word count and links. Price: $0.003 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Web
      externalDocs:
        url: https://fourzerotwo.si/apis/web/read
      parameters:
      - name: url
        in: query
        required: true
        description: Public http(s) URL
        schema:
          type: string
          maxLength: 2000
        example: https://www.gov.uk/government/organisations/hm-revenue-customs
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: sample
      x-mcp-tool: web__read
    servers:
    - url: https://fourzerotwo.si
  /v1/web/unfurl:
    get:
      operationId: web__unfurl
      summary: 'Web Reader: Link preview (unfurl)'
      description: 'Open Graph and Twitter card data, favicon, theme colour, JSON-LD types, RSS/Atom feeds and sitemaps for a URL. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - Web
      externalDocs:
        url: https://fourzerotwo.si/apis/web/unfurl
      parameters:
      - name: url
        in: query
        required: true
        description: Public http(s) URL
        schema:
          type: string
          maxLength: 2000
        example: https://www.bbc.co.uk/news
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.002000'
      x-free-tier: free
      x-mcp-tool: web__unfurl
    servers:
    - url: https://fourzerotwo.si
  /v1/web/url-safety:
    get:
      operationId: web__url_safety
      summary: 'Web Reader: URL safety check'
      description: 'Warning signs for a URL: redirect chain and final destination, TLS certificate, domain age, punycode and brand-lookalike tricks, bare IPs, and security-header grade. Price: $0.003 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - Web
      externalDocs:
        url: https://fourzerotwo.si/apis/web/url-safety
      parameters:
      - name: url
        in: query
        required: true
        description: Public http(s) URL
        schema:
          type: string
          maxLength: 2000
        example: https://www.paypal.com/uk/home
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: free
      x-mcp-tool: web__url-safety
    servers:
    - url: https://fourzerotwo.si
components:
  responses:
    PaymentRequired:
      description: x402 payment required. The body (also base64 in the PAYMENT-REQUIRED header) lists accepted payments.
      headers:
        PAYMENT-REQUIRED:
          schema:
            type: string
          description: Base64 JSON x402 v2 PaymentRequired
      content:
        application/json:
          schema:
            type: object
            properties:
              x402Version:
                type: integer
              error:
                type: string
              accepts:
                type: array
                items:
                  type: object
    Error:
      description: 400 = invalid input, 404 = not found at the source, 502 = the source failed. Never charged.
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                type: string
              charged:
                type: boolean
  securitySchemes:
    freeKey:
      type: apiKey
      in: header
      name: X-API-Key
      description: Optional free key (fzt_…) for the free tier.
x-refined-from:
- openapi.json
- fourzerotwo-si-openapi.json