Layerswap Docs

To confirm the outcome of a swap started from the Hosted Page, check its status through the Layerswap API.

Correlate with `externalId`

Add a unique externalId when you construct the Hosted Page URL:

const sessionId = crypto.randomUUID();
const params = new URLSearchParams({
  to: 'BASE_MAINNET',
  toAsset: 'USDC',
  destination_address: userAddress,
  externalId: sessionId,
});

The created swap stores this value as reference_id. Store the session ID with the user action in your backend. When you list that user’s swaps with GET /swaps, match swap.metadata.reference_id to your stored value and then track the matching swap by ID. reference_id idempotency is unconfirmed, so generate a new value for each attempt and do not treat it as a duplicate-creation guard.

Track by transaction hash

If your application knows the user’s funding transaction hash, call:

curl 'https://api.layerswap.io/api/v2/swaps/by_transaction_hash/0xTRANSACTION_HASH' \
  --header 'X-LS-APIKEY: YOUR_API_KEY'

Then poll GET /swaps/{id} until the swap reaches a terminal state. See Track swaps and Swap lifecycle & statuses.

Let users inspect progress

Link users to the Layerswap Explorer and let them search by swap or transaction identifier. This is useful for support and visibility, but your backend should still verify the API status before crediting a balance or fulfilling an order.

​Correlate with externalId

​Track by transaction hash

​Let users inspect progress

Correlate with `externalId`

Track by transaction hash

Let users inspect progress