402rates

402rates is an x402-native service at https://api.402rates.com, indexed from the x402 Bazaar (Coinbase's public discovery directory). It charges callers itself in USDC on Base and is paid directly at its own wallet; Monex Protocol passes your request and payment headers through untouched. 3 endpoints listed.

Base

Offers

Offer	Endpoint	Price
V1 Ping Paid ping to test the Compass x402 payment rails end to end. Returns pong with server time and the rail you paid on.	`/m/bz-api-402rates-com/v1/ping`	0.001 USDC
Rwa Yields Compare realised 30-day yields of tokenized treasury funds - BUIDL, BENJI, OUSG, USDY, USTB, USYC, VBILL, mTBILL, Spiko EUTBL/USTBL/UKTBL and OpenEden TBILL - computed from each fund's own NAV or price series under the published Open Treasury Yield Basis specification, with every input, window and source disclosed so the figure can be recomputed, and the issuer's own figure printed beside ours.	`/m/bz-api-402rates-com/v1/rwa/yields`	0.03 USDC
Settlement Costs Compare the measured on-chain cost of a USDC transfer across Base, Polygon, Arbitrum, Ethereum, and XDC, using gas units simulated per chain, live gas prices, fresh chain heads and the rollup L1 data fee, sorted cheapest first.	`/m/bz-api-402rates-com/v1/settlement/costs`	0.01 USDC

Machine-readable: openapi.json with x-payment-info offers.

Try it live

Run the full MPP flow from your browser: catch the 402, sign the payment with your wallet, and watch it settle on-chain.

This merchant settles over the mppx rail; pay it from an agent with the snippet below.

Pay with an agent

Any MPP or x402-compatible client works. With mppx, payment is automatic:

import { Mppx, evm } from 'mppx/client'
import { privateKeyToAccount } from 'viem/accounts'

const mppx = Mppx.create({
  methods: [evm({
    account: privateKeyToAccount(process.env.KEY),
    currencies: [evm.assets.base.USDC],
  })],
})

const res = await mppx.fetch('https://api.meshgateway.co/m/bz-api-402rates-com/v1/ping')
// 402 challenge signed and settled automatically; response includes Payment-Receipt

Or inspect the challenge yourself:

curl -i https://api.meshgateway.co/m/bz-api-402rates-com/v1/ping
# HTTP/1.1 402 Payment Required
# WWW-Authenticate: Payment id="…", method="evm", intent="charge", …