You are about to upload and do not know if it will pass.
Check a file against a target site’s upload rules before you submit.
Related searches: document requirement checker, upload validation, file requirements
Same utility over HTTP 402 / x402. Unpaid calls return 402 Payment Required.
POST https://gate402.app/v1/doc-checker
Pay with PAYMENT-SIGNATURE / X-PAYMENT, Stripe MPP (Authorization: Payment), or X-API-Key.