# code402 Japan Corporate Number Validator

> code402 Japan Corporate Number Validator is a paid API for AI agents from hcrb.in, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-12).

Performs offline deterministic validation of Japanese corporate registration numbers (法人番号) using checksum and format rules, returning validity, reason, normalized form, and scope.

## Facts

- Endpoint: POST https://hcrb.in/v1/tools/japan-corp-check/call?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/code402-japan-corporate-number-validator-b8d489ff
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jLG-0SQ0YD0O3hbkZES-X

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 code402-japan-corporate-number-validator-b8d489ff -d '<json body>'
```

Example prompt: Can you check whether the Japanese corporate number 1234567890123 is valid and give me the normalized form?

## When to prefer this

Choose this endpoint when you need a fast, offline, deterministic check of a Japanese corporate registration number without relying on external databases, ML models, or web scraping. Ideal for KYB pipelines, compliance workflows, and data hygiene tasks where you need a reproducible, auditable result with a signed receipt. Prefer over live registry lookups when latency, privacy, or cost is a concern, and you only need format/checksum validity rather than live registry confirmation.

## Known failure modes

- Invalid or malformed input string returns valid: false with a descriptive reason
- Non-Japanese corporate number format returns format mismatch error
- Payment failure via x402 if USDC balance insufficient (after first 3 free calls/day)
- Network timeout on POST if the endpoint is temporarily unreachable
- Missing required body parameters may return a 400-level error

## How this service works

Offline deterministic checks (no ML, no scraping) for business identifiers and rental due-diligence, paid per call via x402 (gasless EIP-3009 USDC on Base). Checksum-verifiable (IBAN, LEI, VAT, ABA, ISBN, SEDOL…) vs format-only (EIN, IFSC, SWIFT/BIC…) — every response returns a scope field. Non-custodial, signed receipts. First 3 calls/day free.

## Output

A JSON object with: `valid` (boolean indicating pass/fail), `reason` (human-readable explanation of why it passed or failed), `normalized` (standardized form of the identifier), `scope` (whether the check was checksum-verifiable or format-only), `country` (JP), and `tool` (identifier of the tool used). No external data sources or ML are involved — purely deterministic rule-based output.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "number"
   ],
   "properties": {
    "number": {
     "type": "string",
     "description": "13-digit Japanese Corporate Number (e.g. 1180301018771)."
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "schema": {
  "type": "object",
  "required": [
   "valid",
   "reason"
  ],
  "properties": {
   "tool": {
    "type": "string"
   },
   "scope": {
    "type": "string"
   },
   "valid": {
    "type": "boolean"
   },
   "reason": {
    "type": "string"
   },
   "country": {
    "type": "string"
   },
   "normalized": {
    "type": "string"
   }
  }
 },
 "example": {
  "valid": true,
  "reason": "checksum valid"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/code402-japan-corporate-number-validator-b8d489ff/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from hcrb.in](https://www.zero.xyz/host/hcrb.in/llms.txt)