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Generate a payment receipt

Selective disclosure receipts let a payer hand a third party, like an accountant or auditor, a JSON file that reveals a specific payment on-chain, without revealing anything else about the payer's shielded activity.

Generating a receipt​

Every prepareTransfer call returns the data needed for a receipt:

const prepared = await session.prepareTransfer({
    inputCommitments: [noteToSpend.commitment],
    amount,
    tokenId,
    recipientDiscoveryData: { evmAddress: recipient },
});

const recipientPending = prepared.executeOptions.recipientPendingNotes[0];
const receipt = {
    commitment:       recipientPending.commitment,
    value:            recipientPending.value,
    tokenId:          recipientPending.tokenId,
    label:            recipientPending.label,
    ownerAddress:     recipientPending.ownerAddress ?? recipient,
    noteSecret:       recipientPending.noteSecret,
    noteAddressHash:  recipientPending.noteAddressHash,
};

const result = await session.relayTransfer(prepared.relayOptions[0]);

const savedReceipt = { receipt, txHash: result.txReceipt.txHash };

The SDK creates a fresh noteSecret for each recipient output while building the proof. Capture the recipient pending note before relay submission, then persist it with the landed transaction hash.

The receipt JSON format​

For accountant-friendly output, wrap the raw note data with payment context:

{
    "type": "privacy-pools-v2-payment-receipt",
    "version": "1",
    "pool": {
        "chainId": 11155111,
        "poolAddress": "0x323C28ce…",
        "tokenId": "0xeeee…eeee"
    },
    "payment": {
        "fromSenderWallet": "0xC9BC5421…",
        "toRecipientWallet": "0x81d48…",
        "amount": "0x7a120",
        "amountFormatted": "0.5 USDC",
        "txHash": "0x…",
        "explorerUrl": "https://sepolia.etherscan.io/tx/0x…"
    },
    "note": { /* the captured receipt data above */ },
    "verification": {
        "commitmentFormula": [
            "noteAddressHash = Poseidon(note.ownerAddress, note.noteSecret)",
            "precommitment   = Poseidon(noteAddressHash, note.tokenId, note.value, 0x0)",
            "commitment      = Poseidon(precommitment, note.label)"
        ],
        "onChainCheck": "PoolVault.commitments(commitment) returns non-zero"
    }
}

Verifying a receipt​

The auditor runs four checks: parsing the JSON, recomputing the noteAddressHash, recomputing the commitment, and confirming the commitment exists on-chain. See the receipt export and audit guide for a complete browser-based verifier implementation.