> ## Documentation Index > Fetch the complete documentation index at: https://docs.knotapi.com/llms.txt > Use this file to discover all available pages before exploring further. # Quickstart > Get started with the TransactionLink integration to retrieve SKU-level transaction data from merchant accounts. If you have already integrated the CardSwitcher product into your application, you can skip the entire client-side integration for TransactionLink and simply begin [retrieving transactions](/transaction-link/quickstart#receive-transactions) from the API. ## Introduction TransactionLink enables you to retrieve SKU-level transaction data from a user's merchant on a recurring basis. With TransactionLink, you can retrieve both historical transactions and new transactions that will occur in the future. You can reference the exact data you'll receive for each transaction [here](/api-reference/products/transaction-link/transaction-object). ## Entry points #### Overview How and where you place entry points to invoke the Knot flow in your app play a crucial role driving engagement and delivering value to end users. Nearly all apps that integrate Knot develop multiple entry points into the Knot flow (e.g. different tabs or screens). As a result and **to provide better visibility into the conversion of the flow across different entry points**, the Knot SDK supports an `entryPoint` parameter when invoking the SDK which allows you to specify the entry point from which the user came. This value is then returned in the down-funnel [`AUTHENTICATED`](/link/webhook-events/authenticated) webhook event, thereby allowing you to measure the conversion of the flow by entry point in your analytics tool of choice. #### Usage It is strongly recommended to take advantage of this functionality, so as to future-proof your visibility into your implementation and allow for future optimizations. To take advantage of this functionality, simply pass a different value to `KnotConfiguration.entryPoint` for each of your entry points when [configuring the session to invoke the SDK](/sdk/ios#configure-the-session). Common entry points include the following: `onboarding`, `home`, `push-notif-X`, `in-app-lifecycle-card-X`, etc. ## Getting started Check out the [Link Account](/api-reference/development/link-account) endpoint to bypass the client-side SDK and quickly link a merchant account & generate transactions in the development environment for testing. ### Start the flow Ensure you have access to your [Customer Dashboard](https://dashboard.knotapi.com) and retrieve your `client_id` and `secret`, which you will use as the basic auth username and password for your API key respectively. Note that your `client_id` and `secret` vary between the`development` and `production` environments. Subscribe to webhooks in your [Customer Dashboard](https://dashboard.knotapi.com) so your backend can be notified about user-generated events, as well as asynchronous processes. You will need to receive these events later on in the flow. Call [List Merchants](/api-reference/merchants/list-merchants) to retrieve a list of merchants that are available for the TransactionLink product by passing `type = transaction_link`. These are merchants you can display in your app and allow users to link. To get started quickly, you can use `merchant_id: 19` for DoorDash to later pass when initializing the SDK. You will be notified via the [`MERCHANT_STATUS_UPDATE`](/link/webhook-events/merchant-status-update) webhook when/if this list changes. Merchant IDs are static and remain constant across all environments. With your `client_id` and `secret` for the `development` environment, call [Create Session](/api-reference/sessions/create-session) with `type: transaction_link` to create a session used when invoking the SDK. Install an SDK of your choosing, for example on iOS [here](/sdk/ios). If you are using the Web SDK, make sure to allowlist your application's domains for the `development` and `production` environments in your [Customer Dashboard](https://dashboard.knotapi.com). Initialize the SDK with the `session_id` retrieved from [Create Session](/api-reference/sessions/create-session) and a merchant `Id` retrieved from [List Merchants](/api-reference/merchants/list-merchants) in `KnotConfiguration` or you can use `merchant_id: 19` for DoorDash to get started quickly. The SDK is where users will interact with the Knot UI to authenticate to various merchants. All login flows, including step-up authentication, are handled within the SDK. Users will see real-time feedback as they progress through authenticating with a merchant. Specifying an exact merchant by passing a merchant `Id` in `KnotConfiguration` when initializing the SDK is required for the TransactionLink product. ### Link a merchant account **In the development environment,** use [testing credentials](/transaction-link/testing) to login to a merchant account and simulate retrieving transactions. Ingest the [`AUTHENTICATED`](/link/webhook-events/authenticated) webhook to notify your backend that the merchant account is successfully linked to Knot and that the connection status is `connected`. Similarly and as applicable, listen to the client-side `onEvent` callback in the SDK to receive the `authenticated` event. You can also use [Get Merchant Accounts](/api-reference/accounts/get-accounts) to retrieve this and other merchant accounts, as well as their connection status. This can be useful to know that you should display the merchant account to the user in their list of linked merchant accounts with the appropriate connection status (i.e. `connected` or `disconnected`). See more about handling disconnected merchant accounts [here](/transaction-link/quickstart#handle-disconnected-merchant-accounts). ## Receive transactions ### New transactions To be notified about new transactions in a merchant account, listen to the [`NEW_TRANSACTIONS_AVAILABLE`](/transaction-link/webhook-events/new-transactions-available) webhook. You will receive this event shortly after a user authenticates to a merchant account for the first time and on any subsequent instance where new transactions are created in the merchant account. Upon receiving the [`NEW_TRANSACTIONS_AVAILABLE`](/transaction-link/webhook-events/new-transactions-available) webhook, make a request (or multiple) to [Sync Transactions](/api-reference/products/transaction-link/sync) to sync new transactions for a user's specific merchant account. **In the development environment**, you will receive 205 new transactions. ### Updated transactions Receiving updated transaction information is entirely optional and may not be relevant for your use case. To be notified about updates to existing transactions, listen to the [`UPDATED_TRANSACTIONS_AVAILABLE`](/transaction-link/webhook-events/updated-transactions-available) webhook. You will receive this event for a merchant account each time there are existing transactions for which data has changed (e.g. `orderStatus: SHIPPED` -> `orderStatus: DELIVERED`). Upon receiving the [`UPDATED_TRANSACTIONS_AVAILABLE`](/transaction-link/webhook-events/updated-transactions-available) webhook with an array of transaction IDs, make a request to [Get Transaction By Id](/api-reference/products/transaction-link/get-by-id) for each transaction ID, passing the ID received in the webhook as a path parameter. ## Refresh transactions Knot refreshes transactions for a user's linked merchant account once per day. If your use case requires more frequent updates, you can call [Refresh Transactions](/api-reference/products/transaction-link/refresh) to refresh transactions on demand. **To test in the development environment**, call [Link Account](/api-reference/development/link-account) to link a merchant account and generate transactions, sync the transactions via [Sync Transactions](/api-reference/products/transaction-link/sync), then call [Refresh Transactions](/api-reference/products/transaction-link/refresh). The [`NEW_TRANSACTIONS_AVAILABLE`](/transaction-link/webhook-events/new-transactions-available) webhook will be sent again and 2 new transactions will be available. ## Handle disconnected merchant accounts To test this behavior in development, use the [Disconnect Account](/api-reference/development/disconnect-account) endpoint. If for example a user changes their password to a merchant account, the `connection.status` in [Get Merchant Accounts](/api-reference/accounts/get-accounts) will be returned as `disconnected` and you will not receive transaction data for the user's merchant account until it is reconnected. If this occurs, you will be notified via the [`ACCOUNT_LOGIN_REQUIRED`](/link/webhook-events/account-login-required) webhook event. You'll want to display a UX in your app to allow users to reconnect their account. For example, you may choose to display a button that says "Reconnect" or similar. ## Transaction matching This section is only relevant if you are building a use case that requires matching Knot's transaction data to your existing transaction records from a card processor or core banking system, for example to [enrich transaction details](/use-cases/enrich-transaction-details) with SKU-level data. If you are using transaction data independently (e.g. for spending insights or rewards), this section does not apply. Each [transaction](/api-reference/products/transaction-link/transaction-object) from Knot represents an order placed at a merchant. To match it to the corresponding card transaction in your system, match on the following fields: | Knot field | Match against | Matching rule | | ----------------------------- | ---------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | | `price.total` | Your transaction amount | Allow a small variance (e.g. within \$0.50) to account for rounding differences, partial authorizations, or post-authorization adjustments like tips. | | `datetime` | Your transaction date | Use a 3-day window. Merchant order dates often differ from card settlement or posting dates by 1-2 days. | | `payment_methods[].last_four` | The last four digits of the user's issued card | Exact match. Use this to confirm the transaction was paid with the card you issued. | | `merchant.name` | Your transaction merchant name (optional) | If your existing transaction record already has a reliable merchant name, use it as an additional matching signal. | ### Filter by order status Before attempting to match, filter transactions from Knot by `order_status`, excluding those with the following values: `CANCELLED`, `REFUNDED`, and `RETURNED`.