Preview fees and sweep

Plan a payment before building it, send exactly what was shown, and empty a wallet with nothing left behind.

Preview, then send that transaction

Python

plan = wallet.propose("u1...", 50_000, memo="Invoice 12")
plan.fee            # zatoshis
plan.paying_out     # total to recipients
plan.spends         # [(pool, value)] notes it would spend
plan.change         # [(pool, value)] change outputs
plan.crossing_value # value that would become public by crossing pools
plan.target_height

txid = await wallet.send_proposal(plan)

propose is local: it sends nothing to the server. send_proposal builds, signs and broadcasts exactly the transaction the proposal describes, so the fee paid is the fee shown. If a note it spends was spent or rolled back since, it raises WalletError and builds nothing. Propose again.

propose_many does the same for up to 50 recipients.

Pool crossings

Each shielded bundle's net value balance is public. When Orchard notes pay an Ironwood receiver, the Orchard bundle shows value leaving and the Ironwood bundle shows it arriving, so the amount is on chain. propose reports it as crossing_value, and the same PrivacyError as send applies unless you pass allow_pool_crossing=True. plan.canonical_crossing is true for ZIP 318 canonical migrations, which are allowed.

Sweep a wallet

Python

plan = wallet.propose_sweep("u1...new-wallet")                 # what is spendable now
plan = wallet.propose_sweep("u1...", mode="everything")         # all or nothing
txid = await wallet.send_proposal(plan)

The fee is taken out of the amount. mode="spendable" leaves notes that are still waiting for confirmations. mode="everything" raises WalletError instead of leaving anything behind, for when the wallet must really end up empty. Sapling notes, which ZecPy only receives, are not swept.