Guide

How to actually pay for a call

The homepage shows what a 402 challenge looks like -- that part needs nothing. Actually paying is different: x402 has no bearer-token shortcut. There's no API key to paste in. You need a crypto wallet with a small amount of USDC in it, and a client that speaks x402. This page covers both ways to get there.

What you'll need

A wallet on Base or Solana holding a small amount of USDC -- a few dollars covers a long session of calls at these prices. No account with TariffMonkee, no signup, no API key. The wallet itself is your credential.

Option A: command line

awal is Coinbase's own agentic wallet CLI -- sign in with email, fund with a card or Apple Pay, pay from the terminal.

# Sign in (one-time, sends a code to your email)
npx awal auth login you@example.com
npx awal auth verify <code-from-email>

# Fund the wallet: opens a UI to pay by card, Apple Pay, or Coinbase,
# or send USDC on Base directly to the address from "npx awal address"
npx awal show
npx awal balance

# Check a price with no payment sent
npx awal x402 details "https://tariffmonkee.com/paid/content?url=https://example.com"

# Pay for real. --max-amount is a safety cap, in atomic USDC (10000 = $0.01)
npx awal x402 pay "https://tariffmonkee.com/paid/content?url=https://example.com" --max-amount 10000

Full command reference: awal CLI docs.

Option B: an AI agent

Describe what you want in plain language; the agent finds the endpoint, sees the price, and pays. A few real options:

npx @coinbase/payments-mcp@latest \
  --client claude-code --auto-config

npx skills add second-state/x402

More generally: any MCP server or agent framework with x402 support can call TariffMonkee the same way -- point it at any /paid/* path from /docs and let it handle the 402.

Once you're set up

Every endpoint, its price, parameters, and output shape: /docs (JSON) or /llms.txt (for an agent reading this site directly). The full catalog with descriptions: /products.