Payment protocols

x402 Testnet

The same request and signing flow as x402, on test networks. Use it to validate pricing, wallet handling, retries, and settlement before launch.

URL segment
x402-testnet
Payment header
PAYMENT-SIGNATURE
Availability
Free and paid plans
Best for
End-to-end testing of agent payments without production funds.

Endpoint URL

https://agent-proxy.alchemy.com/v1/x402-testnet/{projectId}/{endpointSlug}/{path}

Setup

  1. Enable x402 Testnet in the dashboard.
  2. Select Base Sepolia, Solana Devnet, or both.
  3. Enter a testnet recipient address for each network.
  4. Set a test price and save the channel.
  5. Fund the client wallet with test assets on the selected network.

Request flow

  1. The client calls the x402-testnet URL.
  2. AgentPay returns HTTP 402 with testnet payment options.
  3. The client signs a payment and retries with PAYMENT-SIGNATURE.
  4. AgentPay verifies and settles the payment on the test network, then forwards the request.

Notes

  • Use this channel for integration tests, demos, and onboarding new agents.
  • Testnet balances and transactions have no production value.
  • Keep testnet URLs separate from production instructions so clients do not sign for the wrong network.