Rate a call you paid for

Tell this server whether a call you paid for delivered what it promised. Send POST /api/feedback with the required fields tx and verdict and pay $0.001 per call over x402 with USDC on an EVM chain (the paying wallet is the identity). It returns a JSON object with recorded, replaced, item, verdict, settlementTx and 4 more.

Bound to the receipt: give it the settlement transaction from that call's PAYMENT-RESPONSE (or Payment-Receipt) header and a verdict of "good" or "bad", and only the wallet the ledger records as having paid for that exact call can write it - so a rating here is always a real customer about a real purchase. One verdict per settlement transaction (sending another replaces yours, it never stacks). A "bad" verdict requires a reason of at least ten characters and is logged for a human with the sha256 of the bytes that call actually served, so the complaint names a specific answer rather than a bad day. Your words are stored for the operator and are never published; the public tally is counts only. Requires an EIP-3009 payment from the same wallet; the $0.001 is the settlement floor, not a charge for complaining, and every refusal is free.

Category: Payments & x402 · Tags: feedback rating receipt reputation quality x402 · Also found as: rate review report-issue verdict

TRY IN PLAYGROUND →

Parameters

Example request

curl -i -X POST https://agent402.tools/api/feedback \
  -H "Content-Type: application/json" \
  -d '{"tx":"0x2f1fecade9bd945e7817c11e5a34cafe6b349dd8c92a7587efed1de476bddfeb","verdict":"good"}'

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

Example response

{
  "recorded": true,
  "replaced": false,
  "item": "crypto-price",
  "verdict": "good",
  "settlementTx": "0x2f1fecade9bd945e7817c11e5a34cafe6b349dd8c92a7587efed1de476bddfeb",
  "settledAt": "2026-09-03T15:16:06.000Z",
  "amountUsd": 0.01,
  "responseSha256": "7d2a9b1c4e6f8a0b2c4d6e8f0a1b3c5d7e9f1a3b5c7d9e1f3a5b7c9d1e3f5a7b",
  "note": "responseSha256 is sha256 over the exact JSON bytes that call returned. It identifies the answer your verdict is about."
}

From an MCP client

catalog.call {
  "slug": "feedback",
  "params": {
    "tx": "0x2f1fecade9bd945e7817c11e5a34cafe6b349dd8c92a7587efed1de476bddfeb",
    "verdict": "good"
  }
}

The hosted connector at https://agent402.tools/mcp needs a payment for feedback; the stdio package pays it from a wallet or from AGENT402_CREDITS_KEY (wallet only for this tool). Local install: npx -y agent402-mcp.

Errors and behavior

• tx and verdict are 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 or MPP: settlement is cancelled when the tool fails.
• Wallet-only: this tool reaches the network or stored state, so it has no proof-of-work tier.
• Identity-bound: results are keyed to the wallet that signed the payment, so only EVM x402 payments are accepted; credits keys and Tempo are refused.
• A GET or HEAD to /api/feedback returns the same 402 quote, so the price can be read without a body.
• 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?.(false); // keep your own spending ceiling in code
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/feedback", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "tx": "0x2f1fecade9bd945e7817c11e5a34cafe6b349dd8c92a7587efed1de476bddfeb",
    "verdict": "good"
  }),
});

Related tools