Tax ID Validation

Check tax identification number formats for supported countries. Returns pattern results and normalised input without checking registration or check digits.

Pay by wallet (x402) tax-id-validate

Example

Input

{
  "tax_id": "SE556703748501",
  "country_code": "SE"
}

Answer

{
  "valid": true,
  "tax_id": "SE556703748501",
  "normalized": "SE556703748501",
  "format_name": "Momsregistreringsnummer",
  "country_code": "SE",
  "checksum_valid": null
}

Inputs

Field	Type	Required	What it is
`tax_id`	string	Yes	Tax identification number (with or without country prefix)
`country_code`	string	No	ISO 2-letter country code (auto-detected from prefix if omitted)

Output fields

How reliably each field appears in a successful answer.

Field	Type	Appears
`valid`	boolean	Always (present in every successful answer)
`normalized`	string	Always (present in every successful answer)
`format_name`	string	Always (present in every successful answer)
`country_code`	string	Always (present in every successful answer)
`checksum_valid`	boolean	Usually (present for most inputs)
`suggestions`	—	Sometimes (present only for some inputs)

How to call it

The same tool through each route. MCP clients reach it through Strale’s server at https://api.strale.io/mcp; the call below is what the agent sends.

# Needs an API key. max_price_cents caps what this call may cost.
curl -X POST https://api.strale.io/v1/do \
  -H "Authorization: Bearer $STRALE_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
    "capability_slug": "tax-id-validate",
    "inputs": {
      "tax_id": "SE556703748501",
      "country_code": "SE"
    },
    "max_price_cents": 2
  }'

{
  "tool": "strale_execute",
  "arguments": {
    "slug": "tax-id-validate",
    "inputs": {
      "tax_id": "SE556703748501",
      "country_code": "SE"
    },
    "max_price_cents": 2
  }
}

import { Strale } from "straleio";

const strale = new Strale({ apiKey: process.env.STRALE_API_KEY! });
const result = await strale.do({
  capability_slug: "tax-id-validate",
  inputs: {
    "tax_id": "SE556703748501",
    "country_code": "SE"
  },
  max_price_cents: 2,
});

import os
from straleio import Strale, DoRequest

strale = Strale(api_key=os.environ["STRALE_API_KEY"])
result = strale.do(DoRequest(
    capability_slug="tax-id-validate",
    inputs={
        "tax_id": "SE556703748501",
        "country_code": "SE",
    },
    max_price_cents=2,
))

# No account. The first request answers 402 with the price in USDC;
# an x402 client pays it from your wallet and repeats the request.
curl -i 'https://api.strale.io/x402/v2/tax-id-validate?tax_id=SE556703748501&country_code=SE'

Limitations

Format validation only
Validates the number format only. It does not check check digits or confirm the number with the tax authority
Country prefix auto-detection
Country prefix is auto-detected for EU VAT numbers — non-EU TINs require explicit country_code