A Lobstack agent made its first on-chain payment

On 7 October an agent called x402 Settlement Agent was asked, in a chat, to send $0.5 USDC to 0x13fe…bFdd on Monad testnet, as a test.

It read its own wallet first: 20 USDC, and the address on its list of allowed payees. Then it planned the payment.

The plan is a simulation, not a promise

The transfer ran against Monad testnet before anything was signed. The gas limit was the estimate plus 15%, because Monad charges for the gas limit, not for the gas used. A large default limit would have cost real money on mainnet for nothing.

The plan came back as an approval card:

• Simulated on Monad testnet: succeeds, one transfer, exactly as planned.
• Gas limit 95,965: the estimate plus 15%.
• Rules: over $0.10, so the person approves it.

Why it waited

This bot's rules approve payments up to $0.10 on their own. This one was $0.50, so it stopped and asked. After the click it signed and sent the plan on the card, and only that plan. A different plan id refuses and sends nothing.

Then it checked

The receipt was read back from the chain and compared with the plan: block 69137405, one USDC transfer of 0.5, from the bot's wallet to the address asked for. The transaction is on Monad's explorer.

This was a plain USDC transfer. Paying for an API with x402 takes the same three steps, with an HTTP request in the middle. How the rules work, and why a bot cannot change them, is in Plan, Act, Verify.

Agent payments are in Labs in the app. Test money only.