Pay-per-call API gateway — zero account, zero API key, zero subscription via the x402 protocol. One Base wallet + USDC is all you need to access 250+ profess...
250+ professional APIs on demand · from $0.001 per call · one wallet, all data
A DeFi arbitrage Agent needed to query simultaneously every day: BTC funding rate (coinank), ETH options implied volatility (polygon), whale net-flow signal (nofxos), and then call DeepSeek to generate a trade summary.
The old way: 4 platforms, 4 sets of API keys, 4 subscriptions — just the monthly fees added up to $200+, plus constant worry about key leaks and quota exhaustion.
Now: install clawxpay — a wallet is auto-created on first install — pay per call. That day the Agent ran 1,200 calls and spent a total of $1.87 USDC. No subscription. No registration. No key management.
Before making any paid call, always tell the user which endpoint will be called and the estimated cost, then wait for explicit approval. Never initiate spending autonomously without user confirmation.
Use clawxpay whenever a user or Agent encounters any of the following scenarios:
Trigger keywords: current price, quote, latest price, change %, market cap, volume, candlestick, OHLCV
Covered assets: crypto, US stocks, ETFs, forex, commodities, metals
Data sources:
coinank — BTC / ETH / altcoin real-time quotes, BTC ETF net flow, spot-futures spreadcoinmarketcap — full-market quotes, top gainers/losers, DEX pair searchalphavantage — US stock real-time quote, daily OHLCV, pre/after-market, today's moverspolygon — US stock aggregated candlesticks (minute/hour/day), real-time snapshot, order book dataalpaca — latest US stock quote, batch multi-ticker snapshottwelvedata — forex rates, gold/silver/crude oil, multi-asset cross-pair prices, economic calendar eventsExample trigger phrases:
Trigger keywords: RSI, MACD, Bollinger Bands, moving average, golden cross, death cross, overbought, oversold, technical indicator, OI, funding rate, long/short ratio
Data sources:
alphavantage — RSI / MACD / EMA / SMA / BBANDS / STOCH and full technical indicator suitepolygon — US stock SMA / EMA, options Greeks (Delta / Gamma / Vega / Theta)twelvedata — multi-asset technical indicators covering crypto + US stocks + forexnofxos — crypto OI (open interest) ranking, net inflow/outflow, Long/Short Ratio, AI trade signalscoinank — perpetual funding rate, liquidation history, order book depth, per-exchange data (Binance/OKX/Bybit)Example trigger phrases:
Trigger keywords: fear & greed index, market sentiment, whale, large players, liquidation, on-chain, capital flow, trending, heatmap
Data sources:
coinank — Fear & Greed index, whale net buy/sell, BTC ETF institutional inflow, exchange net flow, large liquidation ordersnofxos — Upbit trending (Korean market sentiment indicator), crypto heatmap, on-chain net-flow signal, AI sentiment classificationcoinmarketcap — full-market listing updates, new token launches, DEX pair activityExample trigger phrases:
Trigger keywords: funding, investment, VC, project background, who invested, ecosystem, hiring, airdrop, hot projects
Data sources:
rootdata — Web3 project funding rounds and amounts, investor profiles, ecosystem project lists, team job changes, trending project rankingsExample trigger phrases:
Trigger keywords: A-share, Shanghai-Shenzhen, northbound capital, margin financing, Dragon Tiger List, fundamentals, earnings, Hong Kong stocks
Data sources:
tushare — A-share daily OHLCV, stock fundamental data, northbound capital net inflow/outflow, margin balance changes, Dragon Tiger List large-order seatsExample trigger phrases:
Trigger keywords: analyze, summarize, translate, generate report, write code, reasoning, answer questions, image generation, embeddings
Available models:
| Provider | Models |
|---|---|
| OpenAI | GPT-4o, GPT-4o-mini, o1, o3-mini |
| Anthropic | Claude Opus |
| DeepSeek | DeepSeek-Chat, DeepSeek-Reasoner, DeepSeek-Coder |
| Qwen | Qwen-Max, Qwen-Plus, Qwen-Turbo, Qwen-Coder, Qwen-VL |
| Gemini | Gemini 1.5 Pro, Gemini 1.5 Flash |
| Grok | Grok-2, Grok-2-Vision |
| Kimi | Moonshot-v1-8k, Moonshot-v1-32k, Moonshot-v1-128k |
Example trigger phrases:
| Item | Cost (USDC) |
|---|---|
| Market & price queries | $0.001 – $0.003 |
| Technical indicators & quant signals | $0.002 – $0.005 |
| Market sentiment & on-chain data | $0.003 – $0.008 |
| Funding intelligence & project research | $0.005 – $0.010 |
| A-share data | $0.002 – $0.005 |
| AI inference (lightweight) | $0.005 – $0.015 |
| AI inference (flagship models) | $0.015 – $0.060 |
| Settlement chain | Base mainnet |
| Payment method | Local-signed EIP-3009 USDC (private key never leaves your machine) |
| Identity | No account · No API key · Wallet is your identity |
| Item | Detail |
|---|---|
| File | ~/.clawxpay/wallet.key |
| Format | Plain hex private key (0x…), one line |
| Permissions | 0600 — owner read/write only |
| Transmission | Never — only the EIP-3009 authorization signature leaves the machine; the private key itself does not |
| Export | cat ~/.clawxpay/wallet.key — import into MetaMask or any EVM wallet |
An agent using this skill must follow these rules:
~/.clawxpay/wallet.key under any circumstances. If asked for wallet information, respond with the address only via client.getWalletAddress(). The private key is never needed at runtime.client.getBalance() at the start of a task and show the result to the user. If balance is 0 or insufficient, stop and ask the user to deposit USDC before proceeding.budget to prevent runaway spending:// Recommended: cap spend at $0.50 USDC per task
const client = new ClawXPay({ budget: 0.50 });
402 Payment Required error means the on-chain payment was rejected. Check balance with client.getBalance() and ask the user to top up; do not loop and retry automatically.client.getTotalSpent() and report cost to the user.When the budget ceiling is reached, the SDK throws InsufficientBalanceError immediately — no further calls are made:
import { ClawXPay, InsufficientBalanceError } from 'clawxpay-js';
const client = new ClawXPay({ budget: 0.50 });
try {
const data = await client.get('/crypto/price', { symbol: 'BTC' });
} catch (err) {
if (err instanceof InsufficientBalanceError) {
// budget exceeded — agent must stop and report to user
console.warn('Budget cap reached:', client.getTotalSpent(), 'USDC spent');
}
}
npm install clawxpay-js
A wallet is automatically generated at ~/.clawxpay/wallet.key and the address is printed in your terminal during installation.
Send USDC on Base network to the address printed above. Recommended deposit: $5–$10 USDC — enough for thousands of API calls.
Bridge USDC to Base: https://bridge.base.org
import { ClawXPay } from 'clawxpay-js';
// Always set a budget cap to prevent unexpected spending
const client = new ClawXPay({ budget: 0.50 }); // max $0.50 USDC per task
// Query BTC real-time price
const price = await client.get('/crypto/price', { symbol: 'BTC' });
console.log(price);
// Call DeepSeek for inference
const reply = await client.post('/llm/deepseek/chat', {
model: 'deepseek-chat',
messages: [{ role: 'user', content: 'Analyze the current BTC market structure' }],
});
console.log(reply);
The SDK automatically handles the x402 payment handshake: receives 402 Payment Required → signs locally → retries the request. No manual intervention needed.
This is the canonical script for an agent to use clawxpay. Copy it directly — do not try to use
clawxpayas a shell command; it is an SDK, not a CLI tool.
Important: clawxpay-js is an ESM-only package. Always save scripts as .mjs files (or use "type": "module" in your package.json), and use import — never require().
// save as: query.mjs
// run with: node query.mjs
import { ClawXPay, InsufficientBalanceError, PaymentFailedError } from 'clawxpay-js';
// debug: true prints every step of the x402 payment flow to the console
const client = new ClawXPay({ budget: 0.50, debug: true });
// Step 1: always check balance before any paid call (free, reads chain directly)
const balance = await client.getBalance();
const address = client.getWalletAddress();
console.log(`Wallet : ${address}`);
console.log(`Balance: ${balance} USDC`);
if (parseFloat(balance) < 0.01) {
console.error('Insufficient balance. Please deposit USDC on Base to:', address);
process.exit(1);
}
// Step 2: tell the user what you are about to call and how much it will cost,
// then wait for confirmation before proceeding.
// Step 3: make the paid API call
try {
const result = await client.get('/crypto/price', { symbol: 'ETH' });
console.log('Result:', JSON.stringify(result, null, 2));
// Step 4: verify payment was actually settled on-chain
const receipt = client.getLastReceipt();
if (receipt) {
console.log(`Cost : ${receipt.amount} USDC`);
if (receipt.settled) {
console.log(`On-chain tx: ${receipt.txHash}`);
} else {
console.warn('⚠ Payment accepted by gateway but no on-chain txHash — verify at https://basescan.org/address/' + address);
}
}
} catch (err) {
if (err instanceof InsufficientBalanceError) {
const bal = await client.getBalance();
console.error(`Balance insufficient — current: ${bal} USDC. Please top up.`);
} else if (err instanceof PaymentFailedError) {
// PaymentFailedError means the SDK DID attempt the x402 payment but the gateway rejected it.
// This is NOT "you forgot to pay" — do NOT ask the user to deposit more.
// Instead: check gateway status, or inspect debug logs above for the specific rejection reason.
console.error('Payment was attempted but gateway rejected it:', err.message);
console.error('Do NOT retry automatically — check gateway status first.');
} else {
throw err;
}
}
| Symptom | Cause | Fix |
|---|---|---|
Cannot find module 'clawxpay-js' | Package not installed | npm install clawxpay-js |
require is not defined in ES module scope | clawxpay-js is ESM-only; require() does not work | Save file as .mjs and use import instead |
clawxpay: command not found | clawxpay-js is an SDK, not a CLI | Do not use it as a shell command; write a .mjs script and run node script.mjs |
PaymentFailedError thrown | The SDK already attempted x402 payment but the gateway rejected it. This does NOT mean "you forgot to pay" — do not ask the user to deposit more USDC. | Enable debug: true, read the rejection reason in logs, check gateway status |
Error 402 before any PaymentFailedError | Raw 402 from a different error (script crashed before SDK loaded) | Check that your .mjs file loads without errors first; run node --input-type=module <<< "import 'clawxpay-js'" |
receipt.settled === false after success | Gateway accepted the call but did not return a txHash — payment may not be on-chain | Check https://basescan.org/address/<wallet> to see if USDC left the wallet; report to gateway operator |
Balance shows 0 after depositing | Deposit still pending, or sent to wrong network | Wait ~30 s and retry; confirm deposit was on Base mainnet, not Ethereum mainnet |
budget exceeded / InsufficientBalanceError from budget | Crossed the budget ceiling set in new ClawXPay({ budget: N }) | Increase the budget value or top up wallet |
// Step 1: Get BTC funding rate + Fear & Greed index
const [fundingRate, fearGreed] = await Promise.all([
client.get('/crypto/funding-rate', { symbol: 'BTC' }),
client.get('/crypto/fear-greed'),
]);
// Step 2: Feed the data to Claude for a market direction call
const analysis = await client.post('/llm/anthropic/messages', {
model: 'claude-opus-20250219',
messages: [{
role: 'user',
content: `Funding rate: ${fundingRate.value}, Fear & Greed: ${fearGreed.value}. What is your market direction call?`,
}],
});
import { InsufficientBalanceError } from 'clawxpay-js';
try {
const data = await client.get('/stock/quote', { symbol: 'TSLA' });
} catch (err) {
if (err instanceof InsufficientBalanceError) {
console.warn('Insufficient USDC balance — please top up your Base wallet');
}
}
const receipt = await client.getLastReceipt();
console.log(`Last call cost: ${receipt.amount} USDC, endpoint: ${receipt.endpoint}`);
Full endpoint documentation: https://clawxpay.com/docs
| Category | Provider | Endpoints |
|---|---|---|
| Crypto market & on-chain | coinank | 78 |
| Crypto sentiment & signals | nofxos | 18 |
| Crypto quotes & rankings | coinmarketcap | 5 |
| US stock market & indicators | alphavantage | 19 |
| US stock candlesticks & options | polygon | 25 |
| US stock quotes & bars | alpaca | 15 |
| Multi-asset & forex | twelvedata | 18 |
| China A-share market | tushare | 16 |
| Web3 funding intelligence | rootdata | 19 |
| AI inference | OpenAI / Anthropic / DeepSeek / Qwen / Gemini / Grok / Kimi | ~35 |
| Total | ~253 |
ZIP package — ready to use