An audit trail is a signature certificate from SignEasy, with details on when each signer in a signature request has signed the document and when the request was complete. The audit trail is sent to you over email by default along with the final signed document (only if the signature request was not signed via embedded signing).
Use this API to fetch the audit-trail for a completed signature request, using the signed file ID. This API works on signed documents, even if they are deleted from your account.
The API returns a PDF of the audit trail which you can store for your records.