API Reference

createCloakClient(config)

Returns a CloakClient.

interface CloakConfig {
  publicClient: PublicClient      // viem, required
  walletClient?: WalletClient     // required for deposits
  poolAddress: `0x${string}`
  relayerUrl: string
  chainId: number
  deployBlock?: bigint            // bounds event queries
  store?: NoteStore               // defaults to MemoryNoteStore
}

CloakClient

deposit({ asset, amount }) → Promise<Note>

Funds the pool with a new note. asset is ETH_ADDRESS (0x0…0) for native ETH or a token address. For ERC-20, approval is handled automatically. The user’s wallet signs this transaction. The note is saved to the store and returned.

send(params) → Promise<SendResult>

Forward a transaction (or transfer) through an ephemeral proxy, relayed.

interface SendParams {
  note: Note
  target: `0x${string}`
  data?: `0x${string}`      // omit/"0x" for a plain transfer
  value?: bigint            // amount of the note's asset to spend; default: whole note minus fee
  returnAsset?: `0x${string}` // asset expected back at the proxy (enables claiming)
  fee?: bigint              // relayer fee in the note's asset; default 0
}
 
interface SendResult {
  txHash: `0x${string}`
  changeNote: Note          // persisted automatically
  claimNote?: Note          // present if returns were expected
}

withdraw({ note, to, amount?, fee? }) → Promise<SendResult>

Convenience wrapper over send with an empty calldata transfer to to.

claim({ claimNote, to, fee? }) → Promise<SendResult>

Withdraw a discovered claim note. The claim note must already be harvested on-chain (call sync first).

sync() → Promise<MerkleTree>

Rebuild the Merkle tree from pool events and reconcile stored notes: assign leaf indices to newly-confirmed notes and discover harvested claim notes. Returns the tree.

getNotes() → Promise<Note[]>

Spendable notes (synced, unspent, positive value).

getClaimables() → Promise<Note[]>

Discovered, unspent claim notes ready to withdraw.

relayerInfo() → Promise<RelayerInfo>

Relayer address, pool address, chain id, and minimum fee.

Note

interface Note {
  secret: bigint            // private — losing this loses the funds
  nullifierKey: bigint      // private
  asset: `0x${string}`
  amount: bigint
  leafIndex?: number        // assigned after the commitment is found on-chain
  commitment?: bigint
  kind?: "deposit" | "change" | "claim"
  spent?: boolean
}

Note stores

• MemoryNoteStore — in-memory, lost on reload. Default.
• LocalStorageNoteStore(chainId, poolAddress) — browser localStorage, keyed per chain + pool.
• NoteStore — implement this interface to back notes with your own encrypted storage.

Lower-level exports

For custom flows: proveSpend, verifySpend, MerkleTree, poseidon2, computeCommitment, computeNullifier, computeIntentHash, createNote, cloakPoolAbi, erc20Abi, and the constants FIELD_PRIME, TREE_HEIGHT, ZERO_VALUE, ETH_ADDRESS.

Relayer HTTP API

The SDK talks to the relayer for you, but the endpoints are simple: