Retries

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://retry.exende.dev/v1/retries' \
  -H 'content-type: application/json' \
  --data-raw '{"callback_secret":"client-generated-secret-with-at-least-32-characters","callback_url":"https://agent.example.com/retry-complete","request":{"headers":{},"method":"GET","url":"https://api.example.com/data"},"retry":{"initial_delay_seconds":5,"max_attempts":8,"max_delay_seconds":300,"strategy":"exponential"}}'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - -X POST 'https://retry.exende.dev/v1/retries' \
  -H 'content-type: application/json' \
  --data-raw '{"callback_secret":"client-generated-secret-with-at-least-32-characters","callback_url":"https://agent.example.com/retry-complete","request":{"headers":{},"method":"GET","url":"https://api.example.com/data"},"retry":{"initial_delay_seconds":5,"max_attempts":8,"max_delay_seconds":300,"strategy":"exponential"}}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

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

// Pays at most $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fretry.exende.dev%2Fv1%2Fretries&method=POST
const res = await pay("https://retry.exende.dev/v1/retries", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "callback_secret": "client-generated-secret-with-at-least-32-characters",
    "callback_url": "https://agent.example.com/retry-complete",
    "request": {
      "headers": {},
      "method": "GET",
      "url": "https://api.example.com/data"
    },
    "retry": {
      "initial_delay_seconds": 5,
      "max_attempts": 8,
      "max_delay_seconds": 300,
      "strategy": "exponential"
    }
  }),
});
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://retry.exende.dev/v1/retries",
        json={
            "callback_secret": "client-generated-secret-with-at-least-32-characters",
            "callback_url": "https://agent.example.com/retry-complete",
            "request": {
                "headers": {},
                "method": "GET",
                "url": "https://api.example.com/data",
            },
            "retry": {
                "initial_delay_seconds": 5,
                "max_attempts": 8,
                "max_delay_seconds": 300,
                "strategy": "exponential",
            },
        },
    )
    print(res.status_code, res.text)