Chain Candles

{
  "as_of": 1791459117,
  "as_of_block": 52334885,
  "as_of_iso": "2026-10-08T11:31:57Z",
  "base": {
    "address": "0x4200000000000000000000000000000000000006",
    "decimals": 18,
    "symbol": "WETH"
  },
  "candles": [
    {
      "close": 2562.440508,
      "high": 2564.536011,
      "low": 2562.420829,
      "open": 2564.53549,
      "swaps": 162,
      "t": 1791450000,
      "volume_base": 283.1768169,
      "volume_quote": 723823.9884
    },
    {
      "close": 2554.931473,
      "high": 2562.444764,
      "low": 2554.931469,
      "open": 2562.440275,
      "swaps": 332,
      "t": 1791453600,
      "volume_base": 978.302039,
      "volume_quote": 2495689.547
    },
    {
      "close": 2533.963891,
      "high": 2554.934474,
      "low": 2533.962543,
      "open": 2554.932156,
      "swaps": 409,
      "t": 1791457200,
      "volume_base": 2643.973295,
      "volume_quote": 6707581.103
    }
  ],
  "chain": "base",
  "count": 3,
  "dex": "uniswap_v3",
  "fee": 3000,
  "interval": "1h",
  "interval_seconds": 3600,
  "last_candle_partial": true,
  "note": "Computed by Tanod from public Uniswap v3 Swap events of one pool on Base: open/high/low/close are the pool's post-swap prices, volumes the absolute swapped amounts. DEX prices can differ from centralized exchanges (fees, arbitrage lag, MEV and sandwich trades inside a block, depegs of the quote stablecoin). A candle without swaps carries the previous close with zero volume; the last candle is still forming. Informational only, not investment advice.",
  "pair": "WETH/USDC",
  "pool": "0x6c561B446416E1A00E8E93E221854d6eA4171372",
  "price_unit": "USDC per WETH",
  "quote": {
    "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "decimals": 6,
    "symbol": "USDC"
  },
  "source": "Uniswap v3 swaps on Base (on-chain)",
  "timestamps": "Bucketed by block timestamp (UTC, interval-aligned): each log's blockTimestamp, else estimated from Base's fixed 2 s block time anchored at the latest block."
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://tanod.dev/v1/chain/candles' \
  -H 'content-type: application/json' \
  --data-raw '{"interval":"1h","limit":3,"pair":"WETH/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://tanod.dev/v1/chain/candles' \
  -H 'content-type: application/json' \
  --data-raw '{"interval":"1h","limit":3,"pair":"WETH/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 $0.003 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.003" });
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 $0.003 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Ftanod.dev%2Fv1%2Fchain%2Fcandles&method=POST
const res = await pay("https://tanod.dev/v1/chain/candles", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "interval": "1h",
    "limit": 3,
    "pair": "WETH/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 $0.003 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.003"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://tanod.dev/v1/chain/candles",
        json={
            "interval": "1h",
            "limit": 3,
            "pair": "WETH/USDC",
        },
    )
    print(res.status_code, res.text)