isbn-validate
ISBN-10 / ISBN-13 validation and conversion (ISO 2108 check digits): valid flag, expected check digit, corrected value, both forms, GTIN-14, registration group hint.
Endpoint
GET|POST https://forge-tools.dentreprise.workers.dev/api/isbn-validate
Parameters
| Name | Required | Type | Description |
|---|---|---|---|
isbn | Required | string | ISBN-10 or ISBN-13 |
Example request (unpaid — expect 402)
curl -sS -D - "https://forge-tools.dentreprise.workers.dev/api/isbn-validate?isbn=978-2-07-036822-8"
Example 402 challenge
The same object is also sent as a base64 PAYMENT-REQUIRED header. Amounts are atomic USDC units (6 decimals).
{
"x402Version": 2,
"error": "Payment required",
"resource": {
"url": "https://forge-tools.dentreprise.workers.dev/api/isbn-validate",
"description": "ISBN-10 / ISBN-13 validation and conversion (ISO 2108 check digits): valid flag, expected check digit, corrected value, both forms, GTIN-14, registration group hint.",
"mimeType": "application/json"
},
"accepts": [
{
"scheme": "exact",
"network": "eip155:8453",
"amount": "1000",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"payTo": "0x7B8bf45ac6AcbA6D4CFB626b57D3f5fF3C9C89F7",
"maxTimeoutSeconds": 120,
"extra": {
"name": "USD Coin",
"version": "2"
}
}
]
}Retry with payment
curl -sS "https://forge-tools.dentreprise.workers.dev/api/isbn-validate?isbn=978-2-07-036822-8" \ -H "PAYMENT-SIGNATURE: $PAYMENT"
Example response
{
"format": "ISBN-13",
"valid": true,
"isbn10": "2070368223"
}Related endpoints
openfoodfacts-product
Food product sheet from a barcode (EAN/UPC/GTIN) via Open Food Facts: name, brand, quantity, Nutri-Score, NOVA, Eco-Score, nutriments per 100 g, ingredients, allergens, traces, labels, categories, countries, packaging, image.
gtin-validate
GTIN / EAN-8 / EAN-13 / UPC-A / UPC-E / GTIN-14 validation and normalisation (GS1 check digit): type, expected check digit, corrected code, GTIN-14 and EAN-13 forms, GS1 prefix region, book/coupon flags.