Methods

The @fairblock/stabletrust SDK exposes two clients:

ConfidentialTransferClient: direct onchain transfers with encrypted amounts (sender address visible). Covered below.
AnonymousTransferClient: relay-routed transfers that also hide the sender’s address. Signatures are listed below; see the Unlinkable Transfers guide for usage.

Amount types. confidentialDeposit takes a BigInt (base units, from ethers.parseUnits). confidentialTransfer and withdraw take a number (cast with Number(ethers.parseUnits(...))).

ConfidentialTransferClient

Manages direct onchain interactions with the confidential transfer contract. Amounts and balances are encrypted with homomorphic encryption; the sender’s wallet address remains visible onchain.

Constructor

new ConfidentialTransferClient(rpcUrl, chainId)
new ConfidentialTransferClient(rpcUrl, contractAddress, chainId) // custom deployment

Parameter	Type	Description
`rpcUrl`	`string`	HTTP JSON-RPC endpoint of the network
`contractAddress`	`string`	(optional) Explicit Stabletrust contract address for a custom deployment
`chainId`	`number`	Chain ID. The SDK resolves the contract address from this when not passed explicitly

`ensureAccount(wallet, options?)`

Creates a confidential account onchain (if one doesn’t exist) and waits for finalization. Must be called before any confidential operation.

Returns: { publicKey, privateKey }: derived ElGamal keypair for this wallet.
options.waitForFinalization (default true): wait for the account to be finalized.
options.maxAttempts (default 225): maximum polling attempts.

`getAccountInfo(address)`

Fetches onchain account state: exists, finalized, elgamalPubkey, txId, etc.

`getConfidentialBalance(address, privateKey, tokenAddress)`

Decrypts and returns the available and pending balances.

Returns: { amount, available: { amount, ciphertext }, pending: { amount, ciphertext } }

`confidentialDeposit(wallet, tokenAddress, amount, options?)`

Deposits ERC-20 tokens into the confidential contract. Handles ERC-20 approval automatically. amount is a BigInt in token base units.

Returns: Transaction receipt.

`confidentialTransfer(senderWallet, recipientAddress, tokenAddress, amount, options?)`

Transfers a confidential amount to a recipient. The recipient must have an existing confidential account. amount is a number in token base units.

Returns: Transaction receipt.

`withdraw(wallet, tokenAddress, amount, options?)`

Withdraws from the confidential available balance back to public ERC-20. amount is a number in token base units.

Returns: Transaction receipt.

`getFeeToken()`

Returns the fee-token address for the current chain (address(0) = native currency).

`getNonAnonymousTransferFee()`

Returns the protocol fee for a direct confidential transfer, in the fee token’s base units.

`getPublicBalance(address, tokenAddress)`

Returns the public ERC-20 balance for an address as a BigInt.

AnonymousTransferClient

Routes all operations through the Fairycloak relay, which pays gas (except deposits) and keeps the sender’s wallet address offchain. See the Unlinkable Transfers guide for setup, account-ID rules, and end-to-end examples.

Constructor

new AnonymousTransferClient({ fairycloakUrl, chainId, rpcUrl })

Accounts & keys

Method	Description
`deriveAnonymousKeys(authWallet, accountId)`	Derives the per-account ElGamal keypair `{ publicKey, privateKey }`
`createAccount(authWallet, accountId, elgamalPublicKey, options?)`	Creates a new anonymous account via the relay
`ensureAnonymousAccount(authWallet, accountId, elgamalPublicKey, options?)`	Idempotent create-if-absent; returns `{ accountId, accountInfo, created }`
`updateAuthKeys(authWallet, accountId, { add, remove }, options?)`	Adds/removes authorised signers
`getAnonymousAccountInfo(accountId)`	Onchain state: `exists`, `finalized`, `hasPendingAction`, `txId`, `elgamalPubkey`, `authNonce`
`isAuthorizedSigner(accountId, signerAddress)`	Whether an address is an authorised signer

Balances

Method	Description
`getBalance(accountId, tokenAddress, elGamalPrivateKey)`	Decrypted totals `{ amount, available, pending }`
`getAnonymousBalance(accountId, tokenAddress, elGamalPrivateKey)`	Decrypted balances including raw ciphertexts

Moving funds

Method	Gas paid by	Description
`deposit(authWallet, accountId, tokenAddress, amount, options?)`	User	Deposits tokens into an anonymous account
`transferToPublic(authWallet, accountId, params, options?)`	Relay	Transfers to a public EVM address
`transferToAnonymous(authWallet, senderAccountId, params, options?)`	Relay	Transfers between two anonymous accounts
`applyPending(authWallet, accountId, options?)`	Relay	Moves pending incoming balance into available (call after receiving)
`withdraw(authWallet, accountId, params, options?)`	Relay	Withdraws to a public EVM address
`generateTransferProof(privateKey, params)`	N/A	Generates a transfer proof for manual-proof mode
`generateWithdrawProof(elGamalPrivateKey, params)`	N/A	Generates a withdraw proof for manual-proof withdraws

Prepaid fees

Method	Description
`getFeeToken()`	Currently configured ERC-20 fee token address
`getNonAnonymousTransferFee()`	Fee for a direct (non-anonymous) transfer, raw units
`getAnonymousInlineTransferFee()`	Fee for an anonymous transfer, raw units
`getPrepaidFeeBalance(accountId, token)`	Prepaid fee balance for an account and fee token
`depositFees(authWallet, accountId, amount, options?)`	Tops up the prepaid fee reserve (user pays gas)
`withdrawFees(authWallet, accountId, { token, destination, amount }, options?)`	Withdraws a specific fee-token amount
`withdrawAllFees(authWallet, accountId, { destination }, options?)`	Withdraws all prepaid fee balances across all fee tokens

Request tracking

All relay operations return { request_id, tx_hash, status }.

Method	Description
`waitForRequest(request_id)`	Polls until a terminal state (completed / confirmed / failed)
`getRequestStatus(request_id)`	Current status of a request
`getRequestEvents(request_id)`	Full event history (useful for reconnect/recovery)

Get Started

Confidential Transfers

Protected Execution

Confidential Intelligence

Resources

ConfidentialTransferClient

Constructor

`ensureAccount(wallet, options?)`

`getAccountInfo(address)`

`getConfidentialBalance(address, privateKey, tokenAddress)`

`confidentialDeposit(wallet, tokenAddress, amount, options?)`

`confidentialTransfer(senderWallet, recipientAddress, tokenAddress, amount, options?)`

`withdraw(wallet, tokenAddress, amount, options?)`

`getFeeToken()`

`getNonAnonymousTransferFee()`

`getPublicBalance(address, tokenAddress)`

AnonymousTransferClient

Constructor

Accounts & keys

Balances

Moving funds

Prepaid fees

Request tracking

​ConfidentialTransferClient

​Constructor

​ensureAccount(wallet, options?)

​getAccountInfo(address)

​getConfidentialBalance(address, privateKey, tokenAddress)

​confidentialDeposit(wallet, tokenAddress, amount, options?)

​confidentialTransfer(senderWallet, recipientAddress, tokenAddress, amount, options?)

​withdraw(wallet, tokenAddress, amount, options?)

​getFeeToken()

​getNonAnonymousTransferFee()

​getPublicBalance(address, tokenAddress)

​AnonymousTransferClient

​Constructor

​Accounts & keys

​Balances

​Moving funds

​Prepaid fees

​Request tracking

ConfidentialTransferClient

Constructor

`ensureAccount(wallet, options?)`

`getAccountInfo(address)`

`getConfidentialBalance(address, privateKey, tokenAddress)`

`confidentialDeposit(wallet, tokenAddress, amount, options?)`

`confidentialTransfer(senderWallet, recipientAddress, tokenAddress, amount, options?)`

`withdraw(wallet, tokenAddress, amount, options?)`

`getFeeToken()`

`getNonAnonymousTransferFee()`

`getPublicBalance(address, tokenAddress)`

AnonymousTransferClient

Constructor

Accounts & keys

Balances

Moving funds

Prepaid fees

Request tracking