Crew of the Captain

Crew of the Captain Validation API

The validation API from Crew of the Captain — 6 operation(s) for validation.

GitHub OpenAPI

Operations 6

POST /api/validate/iban IBAN: country length + ISO 13616 mod-97 checksum ($0.001 per call) #
POST /api/validate/eu-vat EU VAT number: per-country format (offline, no VIES); PL also NIP checksum… #
POST /api/validate/pl-nip Polish NIP tax id: 10 digits + weighted mod-11 checksum ($0.001 per call) #
POST /api/validate/pl-regon Polish REGON: 9 or 14 digits + mod-11 checksum ($0.001 per call) #
POST /api/validate/pl-pesel Polish PESEL: checksum + encoded birth date and sex ($0.001 per call) #
POST /api/validate/email Email address syntax (dot-atom local part, LDH domain; no DNS) ($0.001 per call) #

Specifications

⚙
OpenAPI
https://artifacts.apis.io/crewofthecaptain-com/openapi/crewofthecaptain-com-validation-api-openapi.yml

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OpenAPI Specification

crewofthecaptain-com-validation-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: x402 Format Checker Validation API
  version: 1.3.0
  description: Format and checksum validation for IBAN, EU VAT, Polish NIP/REGON/PESEL and email, pay-per-call via x402. Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. No account or API key. Also available as a remote MCP server at https://validate.crewofthecaptain.com/mcp and an A2A agent at https://validate.crewofthecaptain.com/a2a. We never store the values you check; we count requests and public payment data.
  x-guidance: 'POST /api/validate/{type} with JSON {"value": "..."}. An unpaid request returns 402 with a PAYMENT-REQUIRED header; pay with any x402 v2 client and retry with PAYMENT-SIGNATURE. Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base.'
  contact:
    url: https://crewofthecaptain.com
servers:
- url: https://validate.crewofthecaptain.com
tags:
- name: Validation
paths:
  /api/validate/iban:
    post:
      operationId: validate_iban
      summary: 'IBAN: country length + ISO 13616 mod-97 checksum ($0.001 per call)'
      description: Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. Without a valid PAYMENT-SIGNATURE header the server answers 402 with a PAYMENT-REQUIRED header (x402 v2, scheme exact).
      tags:
      - Validation
      x-payment-info:
        price:
          mode: fixed
          currency: USD
          amount: '0.001'
        protocols:
        - x402:
            version: 2
            scheme: exact
            network: eip155:8453
            asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
            payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      x-x402:
        version: 2
        scheme: exact
        network: eip155:8453
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        price: $0.001
        payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - value
              properties:
                value:
                  type: string
                  maxLength: 512
                  example: PL61109010140000071219812874
      responses:
        '200':
          description: Check result (raw input never echoed; personal identifiers masked)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Result'
        '400':
          description: Missing/too-long value or query string present (not charged)
        '402':
          description: Payment required (x402 v2); see PAYMENT-REQUIRED header
        '413':
          description: Body too large (not charged)
        '415':
          description: Content-Type must be application/json (not charged)
  /api/validate/eu-vat:
    post:
      operationId: validate_eu_vat
      summary: 'EU VAT number: per-country format (offline, no VIES); PL also NIP checksum…'
      description: Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. Without a valid PAYMENT-SIGNATURE header the server answers 402 with a PAYMENT-REQUIRED header (x402 v2, scheme exact).
      tags:
      - Validation
      x-payment-info:
        price:
          mode: fixed
          currency: USD
          amount: '0.001'
        protocols:
        - x402:
            version: 2
            scheme: exact
            network: eip155:8453
            asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
            payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      x-x402:
        version: 2
        scheme: exact
        network: eip155:8453
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        price: $0.001
        payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - value
              properties:
                value:
                  type: string
                  maxLength: 512
                  example: PL5260250274
      responses:
        '200':
          description: Check result (raw input never echoed; personal identifiers masked)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Result'
        '400':
          description: Missing/too-long value or query string present (not charged)
        '402':
          description: Payment required (x402 v2); see PAYMENT-REQUIRED header
        '413':
          description: Body too large (not charged)
        '415':
          description: Content-Type must be application/json (not charged)
  /api/validate/pl-nip:
    post:
      operationId: validate_pl_nip
      summary: 'Polish NIP tax id: 10 digits + weighted mod-11 checksum ($0.001 per call)'
      description: Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. Without a valid PAYMENT-SIGNATURE header the server answers 402 with a PAYMENT-REQUIRED header (x402 v2, scheme exact).
      tags:
      - Validation
      x-payment-info:
        price:
          mode: fixed
          currency: USD
          amount: '0.001'
        protocols:
        - x402:
            version: 2
            scheme: exact
            network: eip155:8453
            asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
            payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      x-x402:
        version: 2
        scheme: exact
        network: eip155:8453
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        price: $0.001
        payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - value
              properties:
                value:
                  type: string
                  maxLength: 512
                  example: '5260250274'
      responses:
        '200':
          description: Check result (raw input never echoed; personal identifiers masked)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Result'
        '400':
          description: Missing/too-long value or query string present (not charged)
        '402':
          description: Payment required (x402 v2); see PAYMENT-REQUIRED header
        '413':
          description: Body too large (not charged)
        '415':
          description: Content-Type must be application/json (not charged)
  /api/validate/pl-regon:
    post:
      operationId: validate_pl_regon
      summary: 'Polish REGON: 9 or 14 digits + mod-11 checksum ($0.001 per call)'
      description: Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. Without a valid PAYMENT-SIGNATURE header the server answers 402 with a PAYMENT-REQUIRED header (x402 v2, scheme exact).
      tags:
      - Validation
      x-payment-info:
        price:
          mode: fixed
          currency: USD
          amount: '0.001'
        protocols:
        - x402:
            version: 2
            scheme: exact
            network: eip155:8453
            asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
            payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      x-x402:
        version: 2
        scheme: exact
        network: eip155:8453
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        price: $0.001
        payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - value
              properties:
                value:
                  type: string
                  maxLength: 512
                  example: '123456785'
      responses:
        '200':
          description: Check result (raw input never echoed; personal identifiers masked)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Result'
        '400':
          description: Missing/too-long value or query string present (not charged)
        '402':
          description: Payment required (x402 v2); see PAYMENT-REQUIRED header
        '413':
          description: Body too large (not charged)
        '415':
          description: Content-Type must be application/json (not charged)
  /api/validate/pl-pesel:
    post:
      operationId: validate_pl_pesel
      summary: 'Polish PESEL: checksum + encoded birth date and sex ($0.001 per call)'
      description: Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. Without a valid PAYMENT-SIGNATURE header the server answers 402 with a PAYMENT-REQUIRED header (x402 v2, scheme exact).
      tags:
      - Validation
      x-payment-info:
        price:
          mode: fixed
          currency: USD
          amount: '0.001'
        protocols:
        - x402:
            version: 2
            scheme: exact
            network: eip155:8453
            asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
            payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      x-x402:
        version: 2
        scheme: exact
        network: eip155:8453
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        price: $0.001
        payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - value
              properties:
                value:
                  type: string
                  maxLength: 512
                  example: '44051401359'
      responses:
        '200':
          description: Check result (raw input never echoed; personal identifiers masked)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Result'
        '400':
          description: Missing/too-long value or query string present (not charged)
        '402':
          description: Payment required (x402 v2); see PAYMENT-REQUIRED header
        '413':
          description: Body too large (not charged)
        '415':
          description: Content-Type must be application/json (not charged)
  /api/validate/email:
    post:
      operationId: validate_email
      summary: Email address syntax (dot-atom local part, LDH domain; no DNS) ($0.001 per call)
      description: Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. Without a valid PAYMENT-SIGNATURE header the server answers 402 with a PAYMENT-REQUIRED header (x402 v2, scheme exact).
      tags:
      - Validation
      x-payment-info:
        price:
          mode: fixed
          currency: USD
          amount: '0.001'
        protocols:
        - x402:
            version: 2
            scheme: exact
            network: eip155:8453
            asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
            payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      x-x402:
        version: 2
        scheme: exact
        network: eip155:8453
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        price: $0.001
        payTo: '0xACeaEeBF0Dc8DC7762F2FdE4885f219888e9D045'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - value
              properties:
                value:
                  type: string
                  maxLength: 512
                  example: captain@crewofthecaptain.com
      responses:
        '200':
          description: Check result (raw input never echoed; personal identifiers masked)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Result'
        '400':
          description: Missing/too-long value or query string present (not charged)
        '402':
          description: Payment required (x402 v2); see PAYMENT-REQUIRED header
        '413':
          description: Body too large (not charged)
        '415':
          description: Content-Type must be application/json (not charged)
components:
  schemas:
    Result:
      type: object
      properties:
        type:
          type: string
        valid:
          type: boolean
        normalized:
          type:
          - string
          - 'null'
        reason:
          type: string
        details:
          type: object