Ethereum mainnet · eth_call

Simulate a contract read

0.01 USDC per paid request. Payments settle on Base mainnet; queried data comes from Ethereum.

Preview the price

First install the client. This example uses the Ethereum USDC contract and its decimals() selector.

npx --no-install block402-agent demo simulate quote

The output contains the original request ID and paymentAttempted: false. No wallet key is needed for this step.

Approve, pay and read

Only after the wallet owner approves the purchase or budget and configures a dedicated mainnet buyer wallet:

npx --no-install block402-agent demo simulate pay \
  --request-id REQUEST_ID --allow-pay --budget 0.05

This calls decimals() on Ethereum USDC at latest state. Expected success is 0x followed by a 32-byte encoding of 6. Decode it as an unsigned integer. This is an illustrative interpretation, not a recorded paid result. The call reads state and submits no onchain transaction; it does not predict every outcome of a future transaction.

Recover without another payment

npx --no-install block402-agent demo simulate recover \
  --request-id REQUEST_ID

Repeat the same address or transaction input and the original request ID. Do not authorize another payment after uncertainty. Valid null and empty results are billable.

Short setup walkthrough

This walkthrough shows unpaid quote output, not a paid execution. The commands and interpretation above are its text transcript.

Exact method limits and payment policy