x402.fuchss.app

Trust score (0-100, grade A-F) for any x402 endpoint -- listed in our catalog or not. 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). Uncataloged endpoints are live-probed on your first query and auto-adopted into the monitored catalog (first-contact score with low confidence -- history accumulates from there). Know before you pay.

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).

Find better alternatives to an x402 endpoint. Given a resource URL, returns the top semantically-similar endpoints (matched on advertised purpose via description embeddings) that currently OUT-SCORE it on our deterministic trust score — so an agent about to pay a mediocre endpoint can discover a more reliable, better-settled one serving the same function. Each result carries its trust score, grade, cosine similarity, advertised price and free endpoint-page URL. Same-host siblings and 'avoid'-flagged endpoints are excluded. Returns an empty list (still a valid answer) when nothing beats the subject.

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.

Score up to 50 x402 endpoints in a single paid call. Each found result carries the FULL trust report — identical to POST /v1/x402-trust: score, grade, scoreRange, recommendation, confidence breakdown, the component/subscore breakdown, explanations, flags + flagsDetailed, advertised price, and 30-day on-chain stats — not just the scalar verdict. Cache rows older than 15 minutes are recomputed on-demand from the latest stored probes and settlements, so scores typically reflect reality within minutes. No live network re-probe is performed — for a fresh live probe use /v1/x402-trust. Per-request recompute limits apply (time + count); results include `recomputed` and `computed_at` so you can see which rows used cached vs freshly computed scores. Resources not in our observation set return `found:false`; you still pay for the batch AS LONG AS at least one resource is tracked. If NONE of the supplied resources are in our observation set the request is rejected with HTTP 400 `notCharged:true` and you are NOT charged. Duplicates are ignored.

Semantic search across the entire monitored x402 catalog. Given a free-text query (e.g. "weather forecast", "image generation", "EVM gas price oracle"), returns the closest endpoints by advertised purpose. Ranking is deterministic: cosine similarity bucketed to whole percentage points first (80.3% and 80.5% are the same bucket), then trust score, then described-before-undescribed, then endpoint id. Matches below a 0.5 cosine-similarity floor are dropped entirely, so a query can return fewer than the requested limit (or none). Endpoints that advertise no description are still matched: they are embedded from their service name and URL path tokens instead of a written description (host name as a last resort). The exact effect of a missing description: no fixed point deduction and no direct similarity malus; the only deterministic penalty is the described-before-undescribed tiebreak (at equal similarity bucket AND equal trust score, a described endpoint ranks first). Beyond that it is purely indirect: the shorter fallback text typically yields lower cosine similarity than a prose description, so such endpoints tend to land in lower similarity buckets, by a query-dependent amount. Each match carries its resource URL, trust score, grade, cosine similarity (0-1, raw value; ranking buckets it), advertised description when present, and a free endpoint-page URL. This is a DISCOVERY product: it deliberately carries no verdict, recommendation or flag detail (the per-endpoint trust report sold at /v1/x402-trust carries those). The query is embedded with the same model as the catalog, so phrasing the capability you need works better than guessing keywords.