Check an x402 seller's trust evidence

Trust evidence for any x402 seller origin: is it indexed, does its manifest parse, how many tools does it publish, which chains does it actually advertise, how many settled calls has it been observed receiving on-chain, and would our own Smart Order Router spend buyer money on it, in either of its two lanes: as a proven seller, or through the Base unproven lane (a seller below the settlement floor, tried after every proven candidate under a small per-call ceiling, paid only at the wallet its own live 402 names and flagged unproven on the receipt). routableByOurRouter is true when either lane can pay; routableAsProven is true when some route-execute tier pays it as a proven seller. Send GET /api/x402/seller-trust with the required field origin and pay $0.005 per call over x402 or MPP, or call it free by solving a proof-of-work challenge. It returns a JSON object with origin, listed, displayName, manifestParsed, crawlError and 17 more.

Each lane names the route-execute tiers whose underlying cap covers its routes (lanes.proven.tiers, cheapestTier), with its blockers, so a refusal is explainable. Never fetches the seller at call time - this is our accumulated crawl and settlement evidence, not a liveness probe.

Try in playground →

Parameters

Example request

curl -i "https://agent402.tools/api/x402/seller-trust?origin=agent402.tools"

Without payment this returns HTTP 402 Payment Required with the exact price for seller-trust; any x402 v2 or MPP client pays it and retries.

Example response

{
  "origin": "https://seller.example",
  "listed": true,
  "displayName": "Example Seller",
  "manifestParsed": true,
  "crawlError": null,
  "healthScore": 1,
  "paywall": {
    "ok": true,
    "status": 402,
    "url": "https://seller.example/api/x",
    "at": 1789000000000
  },
  "lastCrawledAt": "2026-10-16T00:00:00.000Z",
  "toolCount": 2,
  "paidToolCount": 2,
  "priceRangeUsd": {
    "min": 0.005,
    "max": 0.02
  },
  "advertisedNetworks": [
    "eip155:8453"
  ],
  "settledCallsObserved": 3,
  "routerGate": {
    "settledCalls": 3,
    "settlementThreshold": 50,
    "meetsSettlementThreshold": false,
    "advertisesSettlementNetwork": true,
    "cheapestPaidToolUsd": 0.005,
    "routerUnderlyingCapUsd": 0.005,
    "hasToolWithinRouterCap": true
  },
  "lanes": {
    "proven": {
      "eligible": false,
      "chain": "base",
      "toolCount": 0,
      "cheapestUsd": null,
      "cheapestTier": null,
      "tiers": [],
      "blockers": [
        "fewer than 50 settled calls observed on-chain"
      ]
    },
    "unproven": {
      "eligible": true,
      "chain": "base",
      "maxUsd": 0.01,
      "toolCount": 1,
      "cheapestUsd": 0.005,
      "cheapestTier": "route-execute",
      "note": "On Base the router may still pay the seller, but only after every proven seller for the task, only at the wallet its own live 402 names, never above that ceiling, and flagged unproven on the buyer's receipt ($0.01 per call)."
    }
  },
  "routableByOurRouter": true,
  "routableAsProven": false,
  "routableVia": "unproven",
  "blockers": [],
  "provenBlockers": [
    "fewer than 50 settled calls observed on-chain"
  ],
  "caveats": [
    "settledCallsObserved counts on-chain payments we have observed to this seller's payTo; it is a floor, not a total"
  ],
  "evidenceSource": "x402 seller crawl + on-chain settlement counts + the router's per-route dispatch verdicts"
}

From an MCP client

catalog.call {
  "slug": "seller-trust",
  "params": {
    "origin": "agent402.tools"
  }
}

On the hosted connector at https://agent402.tools/mcp, catalog.call runs seller-trust free (rate-limited, no wallet). Local install: npx -y agent402-mcp.

Errors and behavior

• origin is required. An input the tool rejects returns an HTTP 4xx whose body carries error, tool, expected, required and example, so the caller can correct it.
• A paid call that ends in any status of 400 or above is not charged over x402, MPP or a prepaid credits key: settlement is canceled when the tool fails. The exception is a Tempo push credential, a transfer the buyer sent before the call: it settles before the tool runs, so if the tool then fails the payment is recorded as a refund owed to the paying wallet.
• Free tier: no outbound network call leaves the server for this tool, so proof-of-work (16 leading zero bits of sha256) pays for it.
• A POST with a JSON body to /api/x402/seller-trust is served as this GET, with the body as the input.
• An Idempotency-Key header makes a retried paid call replay the first 200 instead of charging again (an answer larger than 1 MB is not replayed).

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
client.setSpendControls?.({ maxAmountPerPayment: "$0.005" }); // refuse any quote above this tool's price
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/x402/seller-trust?origin=agent402.tools");

No wallet? Pay with compute

Fetch a challenge, solve the sha256 puzzle (16 leading zero bits, a fraction of a second of CPU), and resend with the X-Pow-Solution header:

import { createHash } from "node:crypto";
const lz = (b) => { let t = 0; for (const x of b) { if (!x) { t += 8; continue; } t += Math.clz32(x) - 24; break; } return t; };
const c = await (await fetch("https://agent402.tools/api/pow/challenge?slug=seller-trust")).json();
let n = 0;
while (lz(createHash("sha256").update(c.challenge + ":" + n).digest()) < c.difficulty) n++;
await fetch("https://agent402.tools/api/x402/seller-trust?origin=agent402.tools", { method: "GET", headers: { "X-Pow-Solution": c.token + ":" + n } });

Related tools