All projects on Base matching “payment header”

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 d

Pay-per-scan AI agent-readability scan. POST { "url": "https://…" } with an X-PAYMENT header to run a scan with no account or subscription. Two tiers: $0.02 (25 pages) and $0.25 (250 pages), USDC on Base.

Cheapest real end-to-end test of your pay-per-call (HTTP 402) client: pay US$0.002, get back what was paid (payer, amount, network, timestamp) and the text you sent; the settlement receipt is in the PAYMENT-RESPONSE header. A free trial call returns paid_usd 0. Use it to check a wallet, a client library or a facilitator before buying something bigger.

Checks an x402 API origin the way x402scan, the CDP Bazaar and agents read it: fetches /openapi.json and /.well-known/x402, then calls each paid route without paying (up to 30) and decodes its 402. Reports routes that do not answer 402, missing or v1-only PAYMENT-REQUIRED headers, prices that differ from the OpenAPI document, resource URLs that differ from the route, wrong USDC EIP-712 domains, mi

Is this x402 endpoint safe to pay? Vet an unknown seller BEFORE paying: pay/avoid verdict, 0-100 trust score, live 402 probe, scam flags (payTo hijack, bait-and-switch pricing, honeypot, wrong asset) and an on-chain check of the receiver on Base. Reads x402 v1 (body) AND v2 (PAYMENT-REQUIRED header) — body-only checkers call live v2 services dead. ?endpoint=url; omit for a trust-ranked catalog.

Use ping when you need a pass/fail verdict that a URL serves expected content: expected HTTP status (default 200), a required body substring, and/or an exact match on one JSON field. One automated fetch at request time, signed receipt with per-condition results. POST the tool inputs as JSON to paid_url with an x402 v2 PAYMENT-SIGNATURE header. See https://docs.cdp.coinbase.com/x402

Lint any x402 endpoint before you pay it: fetches the unpaid 402 challenge (v1 body or v2 PAYMENT-REQUIRED header), decodes price/network/asset/payTo, flags non-USDC assets, testnets, missing bazaar metadata and malformed fields.

x402 pre-listing QA probe: validate your endpoint's 402 challenge, header sizes, and payment schema before listing

Audit a public HTTPS x402 API without payment: HTTP 402 challenge metadata, Bazaar and well-known discovery, OpenAPI 3.1 operation schemas and payment declarations, redirects, latency, and security headers.

Real-time risk-weighted USDC lending APY on Base: Aave/Compound/Morpho read onchain, Moonwell/Euler/Fluid via DefiLlama, source tagged per reading (never estimated). EIP-712 signed by the payment-receiving address (see X-Signal-* headers), which also holds an ERC-8004 identity and attests readings on-chain via EAS. Verified per-asset accuracy is free at /accuracy.json; raw on-chain attestations at

Detect the technologies a website runs — CMS, ecommerce platform, analytics, marketing/CRM, JS framework, hosting/CDN, chat and payments — straight from its public HTML and HTTP headers. No browser, no proxies, no login. Built for sales targeting and competitive research.

Pay-per-call cited research brief. The request carries a query and 1 to 12 quotes with source URLs; the response is a short brief that cites only those quotes, at 0.008 USDC per call on Base. Payment settles after the brief is produced. A client nonce header makes a retry free of a second charge.

Generate a finished, professional invoice PDF from JSON — recipient and line items in, a ready-to-send application/pdf out. Layouts: standard, legal, creative. Totals and tax are computed server-side so the numbers always add up. First payment auto-creates a wallet profile (token + API key in response headers); returning wallets get sequential invoice numbering and can save a sender letterhead. US