fourzerotwo-si

fourzerotwo-si Domains API

Domains & DNS: Is a domain available, who registered it and when, its DNS records, and how well its email is authenticated (SPF, DMARC, MX).

Documentation GitHub OpenAPI

Operations 8

GET /v1/domains/availability Domains & DNS: Domain availability #

GET /v1/domains/facts Domains & DNS: Domain registration facts #

GET /v1/domains/dns Domains & DNS: DNS records #

GET /v1/domains/ip-owner Domains & DNS: IP owner #

GET /v1/domains/dmca-agent Domains & DNS: DMCA agent #

GET /v1/domains/abuse-contacts Domains & DNS: Where to report a site #

GET /v1/domains/email-auth Domains & DNS: Email authentication check #

GET /v1/domains/ideas Domains & DNS: Domain name ideas #

Specifications

⚙

OpenAPI

https://artifacts.apis.io/fourzerotwo-si/openapi/fourzerotwo-si-domains-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Fourzerotwo Si Domains API
  version: 1.1.0
  contact:
    url: https://fourzerotwo.si
  description: 'Operations tagged domains 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: Domains
  description: 'Domains & DNS: Is a domain available, who registered it and when, its DNS records, and how well its email is authenticated (SPF, DMARC, MX).'
paths:
  /v1/domains/availability:
    get:
      operationId: domains__availability
      summary: 'Domains & DNS: Domain availability'
      description: 'Registered or available, straight from the TLD registry. Price: $0.002 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/availability
      parameters:
      - name: domain
        in: query
        required: true
        description: Domain
        schema:
          type: string
          maxLength: 253
        example: some-unregistered-name-402.com
      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: sample
      x-mcp-tool: domains__availability
    servers:
    - url: https://fourzerotwo.si
  /v1/domains/facts:
    get:
      operationId: domains__facts
      summary: 'Domains & DNS: Domain registration facts'
      description: 'Registrar, created, expiry, age, status codes, nameservers and DNSSEC. Price: $0.002 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/facts
      parameters:
      - name: domain
        in: query
        required: true
        description: Domain name (or URL)
        schema:
          type: string
          maxLength: 253
        example: fourzerotwo.si
      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: sample
      x-mcp-tool: domains__facts
    servers:
    - url: https://fourzerotwo.si
  /v1/domains/dns:
    get:
      operationId: domains__dns
      summary: 'Domains & DNS: DNS records'
      description: 'A, AAAA, MX, NS, TXT, CNAME and CAA records (or one type). Price: $0.001 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/dns
      parameters:
      - name: domain
        in: query
        required: true
        description: Domain name (or URL)
        schema:
          type: string
          maxLength: 253
        example: fourzerotwo.si
      - name: type
        in: query
        required: false
        description: A, AAAA, MX, NS, TXT, CNAME, CAA or ALL
        schema:
          type: string
        example: ALL
      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: '0.001000'
      x-free-tier: sample
      x-mcp-tool: domains__dns
    servers:
    - url: https://fourzerotwo.si
  /v1/domains/ip-owner:
    get:
      operationId: domains__ip_owner
      summary: 'Domains & DNS: IP owner'
      description: 'Network, organisation, range, country and abuse email for an IP, from the regional internet registry. Price: $0.002 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/ip-owner
      parameters:
      - name: ip
        in: query
        required: true
        description: IPv4 or IPv6 address
        schema:
          type: string
          maxLength: 45
        example: 8.8.8.8
      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: sample
      x-mcp-tool: domains__ip-owner
    servers:
    - url: https://fourzerotwo.si
  /v1/domains/dmca-agent:
    get:
      operationId: domains__dmca_agent
      summary: 'Domains & DNS: DMCA agent'
      description: 'Published DMCA / abuse contact (email or form) for a major platform, host, CDN or registrar. Price: $0.002 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/dmca-agent
      parameters:
      - name: domain
        in: query
        required: true
        description: Platform domain or URL
        schema:
          type: string
        example: https://www.reddit.com/r/test
      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: sample
      x-mcp-tool: domains__dmca-agent
    servers:
    - url: https://fourzerotwo.si
  /v1/domains/abuse-contacts:
    get:
      operationId: domains__abuse_contacts
      summary: 'Domains & DNS: Where to report a site'
      description: 'Everyone to send an abuse or takedown report to for a site: platform agent, hosting network (+ abuse email, CDN flag) and registrar. Price: $0.005 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/abuse-contacts
      parameters:
      - name: domain
        in: query
        required: true
        description: Domain or URL
        schema:
          type: string
        example: example.com
      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: '0.005000'
      x-free-tier: sample
      x-mcp-tool: domains__abuse-contacts
    servers:
    - url: https://fourzerotwo.si
  /v1/domains/email-auth:
    get:
      operationId: domains__email_auth
      summary: 'Domains & DNS: Email authentication check'
      description: 'MX, SPF and DMARC for a domain, the mail provider, issues found and a grade. Price: $0.003 USDC per call via x402. 3 free calls/day with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/email-auth
      parameters:
      - name: domain
        in: query
        required: true
        description: Domain
        schema:
          type: string
          maxLength: 253
        example: gov.uk
      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: domains__email-auth
    servers:
    - url: https://fourzerotwo.si
  /v1/domains/ideas:
    get:
      operationId: domains__ideas
      summary: 'Domains & DNS: Domain name ideas'
      description: 'Rule-based domain candidates for a keyword: exact, stopword-free, hyphenated, prefixed and suffixed, across chosen TLDs, with a trademark flag. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - Domains
      externalDocs:
        url: https://fourzerotwo.si/apis/domains/ideas
      parameters:
      - name: keyword
        in: query
        required: true
        description: Keyword or phrase
        schema:
          type: string
          maxLength: 100
        example: how to unlock my phone
      - name: tlds
        in: query
        required: false
        description: Comma list of TLDs (default com,co.uk,io)
        schema:
          type: string
          maxLength: 60
        example: com,co.uk
      - name: prefixes
        in: query
        required: false
        description: Comma list of prefixes
        schema:
          type: string
          maxLength: 60
        example: get
      - name: suffixes
        in: query
        required: false
        description: Comma list of suffixes
        schema:
          type: string
          maxLength: 60
        example: hq
      - name: trademarks
        in: query
        required: false
        description: Comma list of brand names to flag
        schema:
          type: string
          maxLength: 200
        example: iphone,samsung
      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: domains__ideas
    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