Quotes & Swaps - LeoKit Documentation

Fetch a Quote

const quote = await sdk.getQuote({
  fromAsset: "ETH.ETH",
  toAsset: "BTC.BTC",
  amount: "1000000000000000000",   // 1 ETH in wei
  destination: "bc1q...",
  origin: "0x...",                 // optional, improves accuracy
  slippageBps: 150,                // optional, 1.5%
});

The returned SwapQuote includes the cheapest/fastest route across all enabled protocols, plus quoteId (used for subsequent executeSwap and tracking calls). AbortSignal is supported for cancellation:

const ctrl = new AbortController();
setTimeout(() => ctrl.abort(), 5000);
const q = await sdk.getQuote(params, ctrl.signal);

Stream Quotes

For UI use cases — display the first quote in ~200ms instead of waiting for every protocol:

const stop = sdk.streamQuote(
  { fromAsset: "ETH.ETH", toAsset: "BTC.BTC", amount: "1000000000000000000" },
  {
    onInit:   (e) => console.log("quote_id:", e.quoteId),
    onQuote:  (e) => console.log(e.protocol, e.data.expected_amount_out),
    onComplete: (e) => console.log("best:", e.quotes[0]),
    onError:  (e) => console.error(e.code, e.message),
  }
);

// Optional: cancel mid-stream
stop();

StreamQuoteCallbacks exposes typed events: StreamingQuoteInitEvent, StreamingQuoteQuoteEvent, StreamingQuoteFinalEvent, StreamingQuoteErrorEvent, StreamingQuoteFinishedEvent. The streaming endpoint is documented at Streaming Quotes.

Execute a Swap

const result = await sdk.executeSwap(quote, {
  // SwapOptions — all optional
  feeOption: "fast",          // fee tier hint (chain-dependent)
  preferredProtocol: "thorchain", // pin a route from the quote bundle
});

SwapResult contains txHash (or txHashes for multi-tx flows like ERC20 approve + swap), the chosen protocol, and any depositInstruction data. ERC20 approvals are auto-handled when needed. The SDK inserts the approval transaction first, then the swap. See the ERC20 approvals guide for details.

Plain Transfer (no swap)

sdk.transfer() sends native or token assets directly without going through a protocol:

const tx = await sdk.transfer({
  asset: "ETH.USDC-0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
  amount: "100",      // 100 USDC
  to: "0xrecipient...",
});
// TransferResult { txHash }

Useful when your app needs simple “move funds” capability that’s not part of a swap.

Transaction Lifecycle

After broadcasting, save the hash so the LeoKit backend can track and emit webhooks:

await sdk.saveTransaction(quote.quoteId, result.txHash);

Poll once:

const status = await sdk.getTransactionStatus(quote.quoteId);
// TransactionStatus { state: "pending" | "success" | "failed" | "refunded", ... }

Or watch with backoff:

const stop = sdk.watchTransaction(quote.quoteId, (status) => {
  if (status.state !== "pending") stop();
}, { intervalMs: 5000, maxIntervalMs: 30000 });

watchTransaction polls /leokit/status and exits cleanly when the swap settles or fails.

Assets & Balances

const all = await sdk.getAssets();             // Asset[]
const usdc = await sdk.getAsset("ETH.USDC-0xA0b...");

await sdk.refreshAssets();                     // forces re-fetch

const bal = await sdk.getBalance("ETH.ETH");           // single
const all = await sdk.getAllBalances();                // every connected wallet × every chain
const slim = await sdk.getBalancesForAddresses([
  { chain: "ETH", address: "0x..." },
  { chain: "BTC", address: "bc1q..." },
]);

The asset list is cached for 20 seconds (per-client); refreshAssets() bypasses the cache.

Events

sdk.on("transaction", (e) => console.log(e.quoteId, e.state));
sdk.on("walletChange", (e) => console.log(e.from, "→", e.to));
sdk.on("error", (err) => console.error(err));

LeoKitEvents is fully typed. Listeners can be removed via the returned Unsubscribe function or sdk.off("transaction", listener).

​Fetch a Quote

​Stream Quotes

​Execute a Swap

​Plain Transfer (no swap)

​Transaction Lifecycle

​Assets & Balances

​Events