# Croatian IBAN Validator (HR, length 21)

> Croatian IBAN Validator (HR, length 21) is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-29).

Validates whether a given string is a mod-97-compliant Croatian (HR) IBAN of exactly 21 characters.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/check-iban-hr?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/croatian-iban-validator-hr-length-21-4a530e0d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gM7KIpDOoAuKBZW4VY8YL

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 croatian-iban-validator-hr-length-21-4a530e0d -d '<json body>'
```

Example prompt: Can you check if HR1723600001101234565 is a valid Croatian IBAN — does it pass the mod-97 checksum and is it the right 21-character HR format?

## When to prefer this

Use this endpoint when you specifically need to validate a Croatian (HR) IBAN. It is narrowly scoped to HR IBANs of length 21, making it precise and cheap ($0.002 USDC). If the IBAN country is unknown, you'd need a general IBAN validator. Prefer the free sandbox POST /v1/sandbox/check-iban-hr endpoint during development and testing before spending on the paid version.

## Known failure modes

- IBAN fails mod-97 checksum — returns invalid
- IBAN length is not exactly 21 characters — returns invalid
- IBAN does not start with HR country code — returns invalid
- Empty or missing input string — returns error
- Input exceeds maximum allowed length — returns validation error

## How this service works

Call when an agent needs whether an IBAN is a mod-97-valid HR number of length 21. Exact $0.002 USDC. Prefer unpaid POST /v1/sandbox/check-iban-hr first.

## Output

Returns a boolean validity result indicating whether the submitted string is a properly formatted Croatian IBAN: exactly 21 characters, starts with 'HR', and passes the mod-97 checksum algorithm.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "description": "JSON value for schema-check SKUs. Omit it on string checks such as email or IBAN."
  },
  "value": {
   "type": "string",
   "examples": [
    "HR48AAAA0000000000000"
   ],
   "maxLength": 20000,
   "minLength": 1,
   "description": "Value to check. The route description names the format: email, phone, IBAN, postal code, VAT, national id, or similar."
  },
  "schema": {
   "description": "JSON Schema document for schema-check SKUs. Omit it on string checks."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/croatian-iban-validator-hr-length-21-4a530e0d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)