fourzerotwo-si Validators API
Validators: Check-digit and format validation for IMEIs, VINs, IBANs, UK phone numbers, UK postcodes and email addresses.
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OpenAPI Specification
openapi: 3.2.0
info:
title: Fourzerotwo Si Validators API
version: 1.1.0
contact:
url: https://fourzerotwo.si
description: 'Operations tagged validators 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: validators
description: 'Validators: Check-digit and format validation for IMEIs, VINs, IBANs, UK phone numbers, UK postcodes and email addresses.'
paths:
/v1/validators/imei:
get:
operationId: validators__imei
summary: 'Validators: IMEI check digit'
description: 'Validate an IMEI (length + Luhn) and split TAC, serial and check digit. Price: $0.0005 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- validators
externalDocs:
url: https://fourzerotwo.si/apis/validators/imei
parameters:
- name: imei
in: query
required: true
description: IMEI
schema:
type: string
maxLength: 20
example: '490154203237518'
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: '0.000500'
x-free-tier: free
x-mcp-tool: validators__imei
servers:
- url: https://fourzerotwo.si
/v1/validators/vin:
get:
operationId: validators__vin
summary: 'Validators: VIN check'
description: 'VIN format, check digit, WMI and model-year candidates. Price: $0.0005 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- validators
externalDocs:
url: https://fourzerotwo.si/apis/validators/vin
parameters:
- name: vin
in: query
required: true
description: VIN
schema:
type: string
maxLength: 20
example: 1HGCM82633A004352
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: '0.000500'
x-free-tier: free
x-mcp-tool: validators__vin
servers:
- url: https://fourzerotwo.si
/v1/validators/iban:
get:
operationId: validators__iban
summary: 'Validators: IBAN check'
description: 'IBAN mod-97 checksum and country length; UK sort code extracted. Price: $0.0005 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- validators
externalDocs:
url: https://fourzerotwo.si/apis/validators/iban
parameters:
- name: iban
in: query
required: true
description: IBAN
schema:
type: string
maxLength: 42
example: GB82 WEST 1234 5698 7654 32
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: '0.000500'
x-free-tier: free
x-mcp-tool: validators__iban
servers:
- url: https://fourzerotwo.si
/v1/validators/uk-phone:
get:
operationId: validators__uk_phone
summary: 'Validators: UK phone number'
description: 'Classify a UK number (mobile, landline, freephone, premium…) and format as E.164. Price: $0.0005 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- validators
externalDocs:
url: https://fourzerotwo.si/apis/validators/uk-phone
parameters:
- name: number
in: query
required: true
description: Phone number
schema:
type: string
maxLength: 20
example: 07700 900123
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: '0.000500'
x-free-tier: free
x-mcp-tool: validators__uk-phone
servers:
- url: https://fourzerotwo.si
/v1/validators/uk-postcode:
get:
operationId: validators__uk_postcode
summary: 'Validators: UK postcode format'
description: 'Validate and normalise UK postcode format; split outward/inward codes. Price: $0.0005 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- validators
externalDocs:
url: https://fourzerotwo.si/apis/validators/uk-postcode
parameters:
- name: postcode
in: query
required: true
description: Postcode
schema:
type: string
maxLength: 10
example: sw1a1aa
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: '0.000500'
x-free-tier: free
x-mcp-tool: validators__uk-postcode
servers:
- url: https://fourzerotwo.si
/v1/validators/email:
get:
operationId: validators__email
summary: 'Validators: Email check'
description: 'Email syntax, whether the domain accepts mail, disposable and role-account flags. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
tags:
- validators
externalDocs:
url: https://fourzerotwo.si/apis/validators/email
parameters:
- name: email
in: query
required: true
description: Email
schema:
type: string
maxLength: 254
example: hello@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: '0.001000'
x-free-tier: free
x-mcp-tool: validators__email
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