See what a past or proposed transaction actually entails.

On Sui, the analyzer reconstructs the programmable block's dataflow graph and runs critical-path, taint, linear-resource, and gas analyses. On Aptos and Movement — account-model chains with no result-chaining — it decodes (the payload, the balance movements, the events, and the write-set) and attributes gas. Everything runs client-side after a single public RPC request.

Set up a transfer the way a wallet would, then see exactly what it does before anything is signed or broadcast: the balances that move, the state it changes, and the gas it costs. Perform a dry run against live chain state.

This is an actual simulated transfer executed against current chain state by the network itself (Sui’s simulateTransaction and the Aptos/Movement simulate endpoint) with signature checks disabled. Nothing is signed and nothing is broadcast; only the RPC request ever leaves the browser.

Attach a spend policy — a cap and an allowlist — and the simulator returns a decision object: allow or deny, bound to these exact parameters, judged against what the transfer actually moves rather than the amount it claims. This is the check an agent’s signer can run before it authorizes an x402 payment: gate on the real effect, refuse (if necessary) before the wallet signs.