x402 · USDC on Base · Live today
x402 gives agents the ability to pay servers directly with USDC. LetAgentPay is the policy layer in front of that wallet — chain allowlists, per-domain caps, category budgets, depeg protection.
Coinbase CDP wallets · Basescan tx links · Same engine for fiat and crypto
Resource server replies with 402 Payment Required and a price quote in USDC.
Agent calls /x402/authorize with chain, domain, amount. Engine checks budget, allowlists, depeg.
On approval, the agent settles USDC on Base. Server verifies tx and returns the resource.
Agent reports tx_hash. LAP corrects budget if actual differs from authorized. Full audit.
from letagentpay import LetAgentPay
client = LetAgentPay(token="agt_...")
auth = client.x402.authorize(
chain="base",
domain="api.example.com",
amount_usdc="0.50",
category="api",
description="Premium endpoint, 1 call",
)
if auth.status == "approved":
# settle on-chain
tx_hash = wallet.send_usdc(
to=auth.recipient,
amount=auth.authorized_amount,
)
client.x402.report(
request_id=auth.request_id,
tx_hash=tx_hash,
)Allow x402 settlements on Base only.
Block .onion domains and any domain
not in (api.openai.com, api.replicate.com,
api.example.com).
Max $0.10 per request, $5/day total
for the "api" category.
Reject any stablecoin trading more than
1% off peg at the time of authorization.Claude converts this to enforceable JSON policy with preview and confirmation before save.
Restrict settlements to chains you trust and merchants you've approved. Wildcard or exact match.
Same budget engine as fiat. APIs, data, infra — different limits per category, all under one cap.
Live exchange rate (Coinbase + CoinGecko). Stablecoin off peg by >1% blocks the authorization.
If actual_amount differs from authorized, the engine corrects budget and prevents tx_hash reuse.
Optional — let LAP provision Coinbase CDP wallets per agent, so the wallet itself is governed.
Switch a flow from x402 to Stripe (or vice versa) without touching governance. One source of truth.
Free during early access. Magic-link signup, no credit card. Test on Base Sepolia before mainnet.