Solverr

AI agents

Price list

Publish your paid endpoints and their prices at /.well-known/solverr.json with @solverr/x402, from a Next.js or Express route, so agents can check prices first.

On this page

A price list at /.well-known/solverr.json tells agents which of your endpoints cost money and how much, so they can decide before they call. @solverr/x402 builds the list and serves it from a Next.js or Express route.

Serve it in Next.js

Create the route file app/.well-known/solverr.json/route.ts and export the result of priceList as its GET handler:

import { priceList } from "@solverr/x402";

export const GET = priceList(
  [
    { path: "/api/premium", method: "GET", price: "0.05", currency: "USD", description: "Premium market data" },
    { path: "/api/report", method: "POST", price: "1.00", currency: "USD", description: "Full company report" },
  ],
  { merchant: "Acme Data" },
);

Serve it in Express

In Express, wrap the price list in expressHandler and register it on the same path:

import { expressHandler, priceList } from "@solverr/x402";

app.get(
  "/.well-known/solverr.json",
  expressHandler(
    priceList([{ path: "/premium", method: "GET", price: "0.05", currency: "USD", description: "Premium market data" }], { merchant: "Acme Data" }),
  ),
);

What agents see

For the Next.js example above, a GET request to /.well-known/solverr.json returns:

{
  "version": 1,
  "merchant": "Acme Data",
  "endpoints": [
    { "path": "/api/premium", "method": "GET", "price": "0.05", "currency": "USD", "description": "Premium market data" },
    { "path": "/api/report", "method": "POST", "price": "1.00", "currency": "USD", "description": "Full company report" }
  ]
}

The response is cached for 5 minutes and allows requests from any origin.

Price list rules

priceList checks every route when it is called and throws on the first mistake:

  • path must start with /.
  • price must have at most 2 decimals.
  • currency must be USD, EUR or INR.

Methods are stored in capitals, whatever case you write them in.

The price list only informs agents. The price actually charged comes from each route's paywall options, so keep the two the same.