x402.fuchss.app

Trust score (0-100, grade A-F) for any publicly listed x402 endpoint. Unlike uptime-only checkers, we return ECONOMIC PROOF: the REAL on-chain USDC settlement volume and distinct-payer count for the endpoint's payTo address — is anyone actually paying it, or is it just live? Computed deterministically from continuous monitoring: 30d probe uptime, 402-envelope spec compliance, latency, observed age, on-chain settlement activity, and advertised-price stability. Includes a full component breakdown, machine-readable flags, and an honest observedDays (we report only the history we actually have, with dataCompleteSince marking our gap-free on-chain coverage). Know before you pay.

x402 payment trace. POST a 0x-prefixed 32-byte tx hash that settled an EIP-3009 transferWithAuthorization or receiveWithAuthorization. The tx + receipt are fetched, the ERC20 Transfer log is decoded, the EIP-3009 selector and payer/payee/amount are extracted, and if the payment was to this reseller the local ledger is cross-checked. Returns schema-pinned JSON: {summary, payment{settled,payer,payee,amountUsd,token,selectorUsed}, route{x402Resource,reseller,knownTo,ourLedgerMatch}, trace{txHash,blockNumber,gasUsed}, observations[], riskFlags[{title,severity,evidence}]}. Multi-chain: base/eth/arb/op/polygon.

Raw observation history for any publicly listed x402 endpoint: discovery snapshots (listed/delisted/relisted, price changes, payTo changes) and probe time-series (uptime, latency, quoted amount) over the requested window (1-90 days).

Monitor ONE x402 endpoint for 30 days and get alerted on changes that break agents: payTo changes (critical — possible takeover/rug), price changes, asset/network changes, 402-spec regressions, delisting, and liveness (down/recovered). Account-free: pay, receive a one-time secret + poll URL. Push to multiple signed HTTPS webhooks and/or Slack/Discord incoming webhooks (up to 5 each per watch). Every push URL is connection-tested before payment — unreachable URLs are rejected with no charge. Edit URLs or cancel early for free via bearer-authed PATCH/DELETE /v1/watch/{id}. Poll the append-only event log; nothing is lost between polls.