Initialize Plaid Items

Before evaluating a payment with Signal, your end users need to link a bank account to your app using Link, Plaid's client-side widget. Link will connect the user's bank account and obtain the consent required to perform this evaluation.

See the Link documentation for more details on setting up a Plaid Link session. At a high level, the steps are:

1. Call /link/token/create with the auth and signal products.

   • (Recommended) To enable the account for use with Signal, and have Signal utilize whatever data is available, put signal in the optional_products array.
   • To require Signal has the maximum data available to it (and reject all Link attempts at institutions that may not provide certain pieces of data), include signal in the products array.
   • If you add Signal to the additional_consented_products array instead, you may need to call /signal/prepare later on; see Adding Signal to existing Items for details.

2. Initialize Link using the link_token created in the previous step. For more details for your specific platform, see the Link documentation. The user will now go through the Link flow.

3. Call /item/public_token/exchange to exchange the public_token for an access_token.

4. Obtain the account_id of the account used for the transaction you wish to perform the evaluation on; this can be obtained from the metadata.accounts field in the onSuccess callback, or by calling /accounts/get or /link/token/get.

Once you have your Plaid Item, continue to evaluate the risk of the transaction.

You may have Items that were not initialized with Signal; for example, if you are adding Signal to an existing Plaid integration. In this case, for best results, call /signal/prepare on the Item before your first call to /signal/evaluate. If you skip calling /signal/prepare, the Item's first call to /signal/evaluate will take longer and be less accurate, because Signal will not have had the opportunity to pre-load certain data about the Item. Subsequent calls to /signal/evaluate on the Item will have higher accuracy.