# Polish PESEL Validator

> Polish PESEL Validator is a paid API for AI agents from x402-test.crewofthecaptain.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12).

Validates the format and checksum of a Polish PESEL (national identification number) via a pay-per-call API

## Facts

- Endpoint: POST https://x402-test.crewofthecaptain.com/api/validate/pl-pesel?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/polish-pesel-validator-52123603
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_W9JZzKBsZ2kkjgBugSm4t

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 polish-pesel-validator-52123603 -d '<json body>'
```

Example prompt: Can you check whether this Polish PESEL number is valid: 44051401458? I need to know if it passes the checksum and what's the normalized form.

## When to prefer this

Use this endpoint when you specifically need to validate Polish PESEL numbers with checksum verification. It is the right choice when building KYC pipelines, onboarding forms, or data quality checks for Polish users, and when you want a pay-per-call model at $0.001 per check rather than maintaining your own validation logic. Prefer this over generic regex checks because it performs full algorithmic checksum validation, not just format matching.

## Known failure modes

- Input value missing or empty — validation may return invalid with a descriptive reason
- PESEL fails checksum — returns valid:false with reason describing the checksum failure
- Malformed input (wrong length, non-numeric characters) — returns valid:false with format error reason
- Payment failure via x402 — HTTP 402 returned if USDC payment on Base is not completed
- Network timeout — service unreachable

## How this service works

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.

## Output

Returns a JSON object with fields: `type` (always 'pl-pesel'), `valid` (boolean indicating pass/fail), `reason` (human-readable explanation such as 'ok' or a description of the error), and `normalized` (the normalized string form of the PESEL).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "value": {
   "type": "string",
   "maxLength": 512
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "type": "pl-pesel",
  "valid": true,
  "reason": "ok",
  "normalized": "…"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/polish-pesel-validator-52123603/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-test.crewofthecaptain.com](https://www.zero.xyz/host/x402-test.crewofthecaptain.com/llms.txt)