Our API is setup so that it's easy to use your own identifier with a particular Credential and your own ID with each recipient.
You may want to use a UID with a recipient so that you can easily map your recipients regardless of changes to their email address.
When creating or updating a Credential, simply pass recipient.id as a field alongside the name and email and we'll store that data for use later.
Please find a full example of creating a Credential here: http://docs.accrediblecredentialapi.apiary.io/#reference/credentials/credentials/create-a-new-credential
You may provide recipient_id as a parameter on our all_credentials endpoint to retrieve Credentials for this recipient later: http://docs.accrediblecredentialapi.apiary.io/#reference/credentials/all-credentials/view-many-credentials
You may want to use your own Credential ID so that you don't need to store our ID in your own database. You'll be able to use your own ID to generate links to the Credential of find and update a Credential.
When creating or updating a Credential, simply pass id as a field at the root level within the credential and we'll store that data for use later. If you don't pass this field we'll assign an auto-generated ID.
Note that this field must be unique per Credential within your account.
You may provide this ID in place of our internal IDs on all endpoints. You can retrieve, update and remove the Credential using your own reference.