x402 paid endpoint

Riddle Oracle

A pay-per-use HTTP endpoint. Send an x402 payment of 0.001 USDC on Base mainnet and the endpoint returns a riddle and its answer. Every settlement is attributed to an ERC-8021 Builder Code, and agents can discover the endpoint automatically through the x402 Bazaar.

GET/api/riddle
Price
0.001 USDC
Network
Base mainnet (eip155:8453)
Scheme
exact
Facilitator
Coinbase CDP
Pay to
PAY_TO_ADDRESS (env)
Builder code
BUILDER_CODE (env, ERC-8021)
Discovery
Listed in the x402 Bazaar

How it works

  1. An unpaid request returns 402 Payment Required with the payment requirements.
  2. An x402 client (or Bazaar-aware agent) signs and submits the 0.001 USDC payment on Base mainnet.
  3. The Coinbase CDP facilitator verifies and settles the payment, attributing the builder code.
  4. The endpoint responds with a riddle and its answer.