# The x402 version 2 402 response

> The shape of an x402 version 2 Payment Required response, with a decoded example and the meaning of every field.

When a resource costs money, an x402 seller answers with HTTP 402 and puts its quote in the `PAYMENT-REQUIRED` response header. The value is base64 of a UTF-8 JSON object. The response body is free-form and clients should not depend on it.

## Headers in the exchange

| Header | Sent by | Carries |
| --- | --- | --- |
| `PAYMENT-REQUIRED` | Seller, on the 402 | The quote: what to pay, to whom, on which network |
| `PAYMENT-SIGNATURE` | Buyer, on the retry | The option it accepted and its signed payment |
| `PAYMENT-RESPONSE` | Seller, on the final response | The settlement result, including the transaction hash |

Version 1 used an `X-PAYMENT` request header and put the quote in the response body. The [endpoint checker](https://x402testendpoint.com/#check) reports which version an endpoint speaks.

## A decoded quote

This is what `https://x402testendpoint.com/t/ok` sends, after base64 decoding:

```json
{
  "x402Version": 2,
  "resource": {
    "url": "https://x402testendpoint.com/t/ok",
    "description": "What is being sold",
    "mimeType": "application/json"
  },
  "accepts": [
    {
      "scheme": "exact",
      "network": "eip155:84532",
      "asset": "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
      "amount": "1000",
      "payTo": "0xSellerWalletAddress",
      "maxTimeoutSeconds": 60,
      "extra": {
        "name": "USDC",
        "version": "2"
      }
    }
  ]
}
```

## Fields

| Field | Meaning |
| --- | --- |
| `x402Version` | `2` for this format. |
| `error` | Optional. Why the previous payment attempt was rejected. See the [error reference](https://x402testendpoint.com/errors). |
| `resource.url` | The URL being paid for. Buyers can compare it with what they requested. |
| `resource.description` | Optional but useful: tells agents and catalogs what is being sold. |
| `accepts` | One or more ways to pay. The buyer picks one it supports. |
| `accepts[].scheme` | How the payment works. `exact` means a fixed amount. |
| `accepts[].network` | A CAIP-2 identifier, such as `eip155:8453` for Base or `eip155:84532` for Base Sepolia. |
| `accepts[].asset` | The token contract address. |
| `accepts[].amount` | The price in the token's smallest unit, as a string. USDC has six decimals, so `1000` is 0.001 USDC. |
| `accepts[].payTo` | The seller's receiving address. |
| `accepts[].maxTimeoutSeconds` | How long the buyer's signed payment should stay valid. |
| `accepts[].extra` | Scheme-specific data. For `exact` on EVM, the token's EIP-712 `name` and `version`, which the buyer needs in order to sign. |
| `extensions` | Optional add-ons, such as the Bazaar extension that lets facilitator catalogs index the endpoint. |

## Check or decode one

- Paste a header into the [header decoder](https://x402testendpoint.com/tools/decode) to see what it contains.
- Run the [endpoint checker](https://x402testendpoint.com/#check) on a URL to validate its quote field by field.
- Fetch a known-good example with `curl -i https://x402testendpoint.com/t/ok`.

Field names and the header encoding follow the types and helpers in `@x402/core` 2.31.

Source: https://x402testendpoint.com/reference/payment-required