X402 · LIVE · BASE MAINNET

x402 — a paid call with a signed receipt

GET /api is a paid call: $0.01 USDC on Base mainnet, x402 v2, scheme exact. Without payment it answers 402 with the offer. With a valid payment it answers the office facts of record and an EdDSA-signed receipt that resolves forever at /x402/receipt/{nonce}.

3
PAID CALLS SETTLED · MAINNET
$0.01 USDC · eip155:8453
PRICE · NETWORK
X402 · THE OFFICE DOOR

The office door

x402 — the office door. Every door in the portfolio answers a request for payment the same way: HTTP 402, the x402 standard, settled in USDC on Base, receipt signed and served forever. This is the office's own door, so a counterparty can prove the loop end to end with the principal's signature on the receipt. One resource: /api returns a signed statement of the office's current holdings summary. Price $0.01. Receipts at /x402/receipt/{nonce}, verified against /x402/jwks.json (kid mk-office-x402-2026-09). Settlement address and amount live in the 402 payload only. The office holds no cryptocurrency: the address is the rail's, the receipt is the office's. Facilitator: Coinbase Developer Platform. Network: Base mainnet.

THE DOOR

What the call buys

  • Route — https://agent-kg.ai/api · GET · 402 without payment, 200 with it
  • Price — $0.01 USDC (10000 units) · Base mainnet eip155:8453 · asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
  • Scheme — exact · EIP-3009 transferWithAuthorization · 60-second window · x402 v2
  • Facilitator — Coinbase CDP (verify, settle) · Bazaar discovery extension on the 402
  • Data — a signed statement of the office's current holdings summary (EdDSA, kid mk-office-x402-2026-09), drawn from /facts.json
  • Receipt — EdDSA-signed, kid mk-office-x402-2026-09, key at /x402/jwks.json, resolves at /x402/receipt/{nonce}
  • Receiver — configured (Worker secret; the address is on the 402 offer)
LAST SETTLEMENT

Paid calls

HOW

One call, one cent, one receipt

  • 1 — GET /api. The answer is 402 Payment Required: the offer in the body and in the PAYMENT-REQUIRED header.
  • 2 — Sign the payment (x402 v2, scheme exact) and repeat the call with the PAYMENT-SIGNATURE header.
  • 3 — The facilitator verifies, the office answers { receipt, data }, the facilitator settles, and PAYMENT-RESPONSE carries the transaction.
  • 4 — The receipt's jwt verifies against /x402/jwks.json; its receipt_url resolves forever.