Free aggregate snapshot of the entire x402 ecosystem (Base + Solana): how many endpoints are listed/active/delisted, what fraction are reachable and spec-compliant, and real on-chain USDC settlement volume / receivers / payers over the last 30 days. Use this to gauge market health before transacting.

Free top-25 most trustworthy x402 endpoints, ranked by a deterministic trust score (uptime, envelope compliance, latency, age, on-chain settlement activity, price stability). Latency is measured from a single EU vantage point and includes network distance to the endpoint (so it is only lightly weighted). Use this to discover reliable paid endpoints.

FREE showcase of what x402_trust_score returns. You do NOT choose the endpoint: this returns the COMPLETE paid-grade trust report (every field — exact score, scoreRange, full component breakdown, advertised price, on-chain settlement figures, all flags) for THREE endpoints picked from the current population — the best-scored, the median, and the worst-scored ('samples' each carry 'role', 'populationRank', and the full 'report'). Use it to see exactly what the paid output looks like across the entire quality range BEFORE paying. It cannot score an endpoint you choose — to evaluate YOUR OWN endpoint, call x402_trust_score (paid). Takes no arguments.

Trust score (0-100, grade A-F, or '?' when unmeasured) for a SPECIFIC x402 endpoint -- cataloged or not (uncataloged endpoints are live-probed on first query, auto-adopted, score carries a low-confidence first-contact flag). PLUS a machine-readable verdict ('recommendation': proceed|caution|avoid|parameterize|unverified|not-payable), the advertised price ('advertised.amountUsd'), a confidence-adjusted band ('scoreRange'), and structured flags ('flagsDetailed' with code/severity/message; any severity 'error' means avoid). The 'parameterize' verdict (with 'templated':true) means the resource URL still contains an unresolved template placeholder (e.g. {slug}, :slug or %7B…%7D) but we DO have a real signal (scored probes or a discovery fallback): substitute a valid value first, then the health metrics apply to the resolved URL. The 'unverified' verdict (grade '?') means we have NO measurement at all (every probe excluded and no discovery payment requirements to fall back on): it is unknown, not bad, so verify the endpoint yourself before paying. The 'not-payable' verdict (grade '?') means the URL answers a 402 with an EMPTY accepts[] (an auth/API-key gate such as sign-in-with-x), so it is not an x402-payable resource at all and there is nothing to settle. For templated per-item endpoints that ARE payable, a varying payTo/price is EXPECTED (one wallet/price per item): the report surfaces 'stats.payToVaries'+'payToDistinct30d' and 'advertised.amountRange30d' as a 'payto-varies'/'price-varies' note rather than a 'payto-changed-recently' hijack error; always pay the payTo in the live 402 quote, not a cached listing. 'stats.scoredProbes30d' vs 'stats.excluded30d' show how many probes actually back the score. Includes the full component breakdown, the provider-advertised 'serviceName' and 'description' (unverified provider claims, shown next to our independent metrics), and 30-day on-chain stats. Note: 'stats.avgLatencyMs' is measured from a single EU vantage point and includes network distance to the endpoint (see 'stats.latencyVantage'), so a geographically distant endpoint reads slower even when its server is fast. One call answers WHETHER and at WHAT PRICE to use an endpoint. Call this BEFORE paying an unknown x402 endpoint to avoid dead, fraudulent, or recently-hijacked services. Pay-per-call over x402; auto-pays if a wallet is configured, otherwise returns the price quote.

Raw observation time-series for a SPECIFIC x402 endpoint: listing/delisting/relisting events, advertised price changes, payTo changes, and probe results (uptime, latency, quoted amount) over the requested window (1-90 days). Per-probe 'latencyMs' is measured from a single EU vantage point and includes network distance to the endpoint. Pay-per-call over x402; auto-pays if a wallet is configured, otherwise returns the price quote.

Given an x402 endpoint URL, returns the top semantically-similar endpoints (matched on advertised purpose via description embeddings) that currently OUT-SCORE it on the deterministic trust score. Use this to route away from a mediocre/dead/expensive endpoint toward a more reliable, better-settled one serving the SAME function — e.g. before paying, check if a higher-graded equivalent exists. Each alternative carries its trust 'score', 'grade', 'recommendation', cosine 'similarity' (0-1), 'amountUsd' price, and a free 'endpointPage' URL. Same-host siblings and 'avoid'-flagged endpoints are excluded. An empty 'alternatives' array is a valid answer meaning nothing beats the subject. Similarity is independent of latency/geography. Pay-per-call over x402 (~$0.005); auto-pays if a wallet is configured, otherwise returns the price quote.

Free-text SEMANTIC SEARCH across the entire monitored x402 endpoint catalog. Given a plain-language query (e.g. "weather forecast", "image generation", "EVM gas price oracle"), returns the up to 25 endpoints whose advertised purpose is semantically closest. Ranking is deterministic and fully specified: cosine similarity bucketed to whole percentage points first (80.3% and 80.5% are the same bucket, so sub-percent noise never outranks a better endpoint), then trust score (0-100), then described-before-undescribed, then endpoint id as a stable final tiebreak. 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 either; 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 the effect is purely indirect: the shorter fallback text typically yields lower cosine similarity than a prose description, so undescribed endpoints tend to land in lower similarity buckets, by a query-dependent (never fixed) amount. Use this for DISCOVERY: find candidate endpoints for a capability before checking any of them in depth. Each match carries 'id', 'resource' URL, trust 'score' (0-100), 'grade' (A-F), raw cosine 'similarity' (0-1; ranking buckets it to whole percents), 'description' when advertised, and a free 'endpointPage' URL. 'score'/'grade' are null for endpoints not yet scored. Deliberately NO verdict/recommendation or flag detail: the per-endpoint trust report (x402_trust_score) carries those. Pay-per-call over x402 (~$0.001); auto-pays if a wallet is configured, otherwise returns the price quote.

Score up to 500 x402 endpoints in a SINGLE paid call. Returns the authoritative full-density trust score (0-100, grade A-F or '?' when unmeasured, recommendation proceed|caution|avoid|parameterize|unverified|not-payable), confidence, probed_at, computed_at, and a recomputed flag for each requested resource. Cache rows older than ~15 minutes are recomputed on-demand from the latest stored probes and settlements (no live network re-probe), so bulk scores typically reflect reality within minutes. Per-request recompute limits apply: at most 50 endpoints / 8 seconds are recomputed; the response includes recompute_limit_hit and recompute_limit so you know if the cap was reached. The smallest tier that fits your request is selected automatically (10/50/100/200/500 endpoints; ~$0.045/$0.20/$0.325/$0.40/$0.50). Resources not in our observation set return found:false; you still pay for the batch. For a fresh live probe, use x402_trust_score. Pay-per-call over x402; auto-pays if a wallet is configured, otherwise returns the price quote.

Start monitoring ONE x402 endpoint for 30 days. Get alerted on changes that break autonomous payment: payTo changes (possible takeover/rug — but for a templated per-item endpoint a payTo move is expected variance and is delivered as severity 'warn', not 'critical'), price changes, asset/network changes, 402-spec regressions, delisting, and liveness down/recovered. A self-healing endpoint that repeatedly blips is auto-detected as liveness_flapping and its individual down/up alerts are coalesced into a single flapping notice (plus one 'stopped flapping' notice when it stabilizes) so you are not spammed. Returns a one-time bearer secret + poll URL + renew URL + edit URL + cancel URL + machine-readable next_steps. Use x402_watch_events to poll the append-only log, or configure push delivery to one or more signed HTTPS webhooks and/or Slack/Discord incoming webhooks (max 5 each). webhook_url/slack_url accept a single URL string or an array of URLs. All URLs are connection-tested BEFORE payment — unreachable URLs are rejected with no charge (retry with a corrected URL). On success the response reports per-URL delivery in delivery.connection_test. Webhook signature: x-signature = 'sha256=' + HMAC-SHA256(body) keyed by hex(sha256(secret)), NOT the raw secret. Pay-per-call over x402 (~$0.20); auto-pays if a wallet is configured, otherwise returns the price quote.

Read the append-only event log for an active x402 watch. Returns two streams: events (endpoint changes — payTo/price/asset/spec/delisting/liveness) and watch_events (lifecycle feedback — created/edited/cancelled/renewed/expiring/expired). Nothing between two polls is lost. Provide the watch_id and the one-time secret from x402_watch_create. Advance since with the returned next_cursor (endpoint events) and watch_since with watch_events_cursor (lifecycle events). Cursors/ids are GLOBAL sequences shared across watches (a watch's first event id may be >1); always page by the returned cursor rather than assuming they start at 1. Cancelled watches remain READABLE until expires_at (no new events accrue). If the watch has push delivery, still poll to reconcile missed webhooks.

Edit an active watch: change webhook/Slack URLs, liveness sensitivity, or subscribed events. Bearer-authed with the secret from x402_watch_create. Newly-added URLs are connection-tested before the change is persisted; if any new URL fails, the existing config is unchanged. Delivery fields are full-replace per channel (omit to leave that channel unchanged). Returns the updated watch view.

Soft-cancel a watch immediately: no new events accrue, but the event log stays READABLE via x402_watch_events until the original expires_at (cancel is not a delete). Probing drops back to normal cadence as soon as no active watches cover the endpoint. Bearer-authed with the secret from x402_watch_create. Free and idempotent.

Extend an active x402 watch by another 30 days before it expires. The secret stays the same. Pay-per-call over x402 (~$0.20); auto-pays if a wallet is configured, otherwise returns the price quote.