Authentication - Arrays

Arrays supports two authentication modes.

1. API Key (recommended for most users)

Send your key in the X-API-Key header.

cURL
Python
Node.js

curl "https://data-tools.prd.arrays.org/api/v1/stocks/company/detail?symbol=AAPL" \
  -H "X-API-Key: $ARRAYS_API_KEY"

import requests, os
r = requests.get(
    "https://data-tools.prd.arrays.org/api/v1/stocks/company/detail",
    headers={"X-API-Key": os.environ["ARRAYS_API_KEY"]},
    params={"symbol": "AAPL"},
)

const res = await fetch(
  "https://data-tools.prd.arrays.org/api/v1/stocks/company/detail?symbol=AAPL",
  { headers: { "X-API-Key": process.env.ARRAYS_API_KEY } }
);

Get a key

Sign up at arrays.org (email, Google, or GitHub)
Copy the key from your Dashboard — visible immediately
Store in env / secret manager — never commit to git

Security best practices

Never expose your API key in client-side code (browser, mobile, public Cursor rules).
Use a backend proxy if you need to call Arrays from a browser app.
Rotate keys regularly from the Dashboard.
Use separate keys for dev / staging / prod.

2. Nanopayment (no key, pay-per-call)

For 15 crypto endpoints, you can skip the API key entirely and pay per call in USDC (Base, via Circle Gateway) or USDC / USDT / USD1 on BNB Chain, using the x402 v2 protocol. Use the dedicated x402 host — it answers a plain GET with 402 Payment Required:

https://x402-data-tools.prd.arrays.org

import { wrapFetchWithPayment } from "x402-fetch";

const fetchWithPayment = wrapFetchWithPayment(fetch, walletClient);
const res = await fetchWithPayment(
  "https://x402-data-tools.prd.arrays.org/api/v1/crypto/funding-rate?symbol=BTCUSDT"
);

The API-key host data-tools.prd.arrays.org returns 401 to a bare request. It will negotiate x402 only if you send Accept-Payment: x402.

Full Nanopayment guide →