Defi Borrow Rates

{
  "cheapest": [
    {
      "available_usd": 1765486,
      "borrow_apy_pct": 5.574,
      "borrow_incentives_pct": 5.79,
      "chain": "Aptos",
      "deposit_apy_pct": 1.616,
      "max_ltv": 0.8,
      "net_cost_pct": -0.217,
      "pool": "5a97dc57-ea99-4d8b-aac9-b1b8b80c6b60",
      "protocol": "echelon-market",
      "token": "USDC",
      "utilization_pct": 44.6
    },
    {
      "available_usd": 2348842,
      "borrow_apy_pct": 3.835,
      "borrow_incentives_pct": 0,
      "chain": "Arbitrum",
      "deposit_apy_pct": 3.026,
      "max_ltv": 0,
      "net_cost_pct": 3.835,
      "pool": "d9c395b9-00d0-4426-a6b3-572a6dd68e54",
      "protocol": "compound-v3",
      "token": "USDC",
      "utilization_pct": 84.1
    }
  ],
  "markets": 41,
  "network": null,
  "note": "Net cost = borrow APY minus incentives. High utilization = the rate can rise fast. Source: DefiLlama.",
  "token": "USDC"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.vextorium.com/v1/defi-borrow-rates' \
  -H 'content-type: application/json' \
  --data-raw '{"limit":5,"token":"USDC"}'

# 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/v1/defi-borrow-rates' \
  -H 'content-type: application/json' \
  --data-raw '{"limit":5,"token":"USDC"}' \
  | 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 $0.006 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.006" });
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 $0.006 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.vextorium.com%2Fv1%2Fdefi-borrow-rates&method=POST
const res = await pay("https://api.vextorium.com/v1/defi-borrow-rates", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "limit": 5,
    "token": "USDC"
  }),
});
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 $0.006 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.006"})
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/v1/defi-borrow-rates",
        json={
            "limit": 5,
            "token": "USDC",
        },
    )
    print(res.status_code, res.text)