$0.000999 per call · 20 free calls/day · no signup · pay with card credits or a signed USDC voucher (x402)
Validate an EAN-13 barcode by its mod-10 checksum (odd positions x1, even positions x3).
curl -X POST https://code402.dev/v1/tools/ean13-check/call \
-H "content-type: application/json" \
-d '{"code":"5901234123457"}'
No key needed for the free tier. When the free quota is used up, the API replies HTTP 402 with the exact price — agents sign the x402 voucher and retry; humans buy card credits. Every paid response carries a signed receipt you can verify offline.
| Field | Type | Meaning |
|---|---|---|
code (required) | string | 13-digit EAN-13 barcode; spaces/dashes allowed. |
Top-level fields: tool, valid, normalized, country, reason, scope. Paid responses also carry a signed XDR-1 receipt.
Machine-readable catalog: llms-full.txt · MCP manifest · OpenAPI. Operated by JUANA LIMITED (UK Co. No. 14043409). Non-custodial: USDC settles payer→seller directly on Base.