StillCurrent

Endpoints (8 live)

• POST /check/citation — Checks whether a quoted sentence or a claim still appears on the cited page (HTML, PDF or text). Exact, punctuation-insensitive and fuzzy quote matching with snippet; lexical claim check incl. every number; compares with the latest archive.org snapshot when missing; includes the full URL liveness/staleness check. (0.02 USDC on Base)
• POST /check/urls — Link triage for up to 25 URLs in one call: HTTP status, redirect chain (up to 4 hops), page title, and a verdict per URL (live, redirected, redirected_cross_domain, moved_to_homepage, dead, blocked, server_error, unreachable, ...). Lighter than /check/url: no archive.org lookup or last-updated date. Use it to find which links in a document need a full check. (0.1 USDC on Base)
• POST /verify/payment — Verify a claimed USDC payment on Base: given a tx hash (or an x402 PAYMENT-RESPONSE header) and what you expect (payee, payer, amount, time window, confirmations), reads the chain and returns match / mismatch / not_settled / not_found with per-field checks, finality, the x402 EIP-3009 pattern, a self-payment flag and a second-RPC cross-check. Cannot show who owns an address or that a service was delivered. (0.02 USDC on Base)
• POST /check/url — Checks whether a URL (source, citation or dataset) is still alive and current: HTTP status and redirect chain, soft-404 / parked-domain / redirect-to-homepage detection, last-updated date from metadata or page text, latest archive.org snapshot, and a verdict (live, live_stale, dead, moved_to_homepage, soft_404, blocked, ...) with evidence. (0.01 USDC on Base)
• GET /verify/payment (0.02 USDC on Base)
• GET /check/urls (0.1 USDC on Base)
• GET /check/citation (0.02 USDC on Base)
• GET /check/url (0.01 USDC on Base)