Curva Tesoro Eeuu Pago

{
  "comparado_con": "2026-09-01",
  "curva": [
    {
      "cambio_pb": 21,
      "plazo": "1 Mo",
      "tipo_pct": 4.06
    },
    {
      "cambio_pb": 22,
      "plazo": "1.5 Month",
      "tipo_pct": 4.1
    },
    {
      "cambio_pb": 24,
      "plazo": "2 Mo",
      "tipo_pct": 4.13
    },
    {
      "cambio_pb": 25,
      "plazo": "3 Mo",
      "tipo_pct": 4.17
    },
    {
      "cambio_pb": 29,
      "plazo": "4 Mo",
      "tipo_pct": 4.26
    },
    {
      "cambio_pb": 27,
      "plazo": "6 Mo",
      "tipo_pct": 4.27
    },
    {
      "cambio_pb": 26,
      "plazo": "1 Yr",
      "tipo_pct": 4.44
    },
    {
      "cambio_pb": 39,
      "plazo": "2 Yr",
      "tipo_pct": 4.78
    },
    {
      "cambio_pb": 45,
      "plazo": "3 Yr",
      "tipo_pct": 4.91
    },
    {
      "cambio_pb": 46,
      "plazo": "5 Yr",
      "tipo_pct": 5.01
    },
    {
      "cambio_pb": 46,
      "plazo": "7 Yr",
      "tipo_pct": 5.12
    },
    {
      "cambio_pb": 45,
      "plazo": "10 Yr",
      "tipo_pct": 5.24
    },
    {
      "cambio_pb": 37,
      "plazo": "20 Yr",
      "tipo_pct": 5.64
    },
    {
      "cambio_pb": 34,
      "plazo": "30 Yr",
      "tipo_pct": 5.61
    }
  ],
  "diferencial_10a_2a_pb": 46,
  "diferencial_10a_3m_pb": 107,
  "fecha": "2026-10-01",
  "fuente": "U.S. Department of the Treasury, Daily Treasury Par Yield Curve Rates (dominio público)",
  "invertida_2a_10a": false
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.vextorium.com/curva-tesoro-eeuu-pago' \
  -H 'content-type: application/json' \
  --data-raw '{"dias_comparar":30}'

# 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://api.vextorium.com/curva-tesoro-eeuu-pago' \
  -H 'content-type: application/json' \
  --data-raw '{"dias_comparar":30}' \
  | 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 $0.004 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.004" });
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 $0.004 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.vextorium.com%2Fcurva-tesoro-eeuu-pago&method=POST
const res = await pay("https://api.vextorium.com/curva-tesoro-eeuu-pago", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "dias_comparar": 30
  }),
});
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 $0.004 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.004"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://api.vextorium.com/curva-tesoro-eeuu-pago",
        json={
            "dias_comparar": 30,
        },
    )
    print(res.status_code, res.text)