# Strale VAT Number Format Validator

> Strale VAT Number Format Validator is a paid API for AI agents from api.strale.io, paid per call via x402, $0.0216/call, status unknown (last checked 2026-09-15).

Validates the format of a VAT number (including country prefix) against country-specific rules for 27+ countries

## Facts

- Endpoint: GET https://api.strale.io/x402/v2/vat-format-validate
- Price: $0.0216/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/strale-vat-number-format-validator-46123b8d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NTwaAbBtuIV3lchmj7ANs

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability strale-vat-number-format-validator-46123b8d
```

Example prompt: Can you check whether the VAT number SE556703748501 is correctly formatted?

## When to prefer this

Choose this endpoint when you need a fast, auditable, format-level VAT number check across 27+ countries without needing real-time registry lookup. Ideal for pre-invoice validation, supplier onboarding, and compliance workflows where you need a cryptographic audit trail of each check. Prefer over manual regex validation or unaudited validators when tamper-evident records matter.

## Known failure modes

- Missing or malformed vat_number parameter returns a validation error
- Unsupported country prefix returns an error indicating the country is not covered
- Purely syntactic/format check — does not confirm the number is registered with a tax authority
- Network timeout or service unavailability returns a 5xx error

## How this service works

The trust layer for AI agents — 250+ independently tested data capabilities across 27 countries. Execute capabilities via REST, MCP, A2A, or x402 micropayments. Every call returns an audit record with cryptographic chain hashing.

## Output

Returns whether the provided VAT number is valid according to the format rules for the indicated country prefix, along with an audit record containing a cryptographic chain hash for traceability.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "vat_number"
     ],
     "properties": {
      "vat_number": {
       "type": "string",
       "description": "VAT number including country prefix (e.g. SE556703748501)"
      }
     }
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/strale-vat-number-format-validator-46123b8d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.strale.io](https://www.zero.xyz/host/api.strale.io/llms.txt)