The Attachment Request feature allows you to request recipients to upload files when signing their documents. This is particularly useful when you need additional documentation such as ID cards, driving licenses, payment receipts, or other supporting documents as part of your signature request.Attachment requests are configured at the envelope level.Once you have created an envelope and set a recipient using signing steps, you will get the recipient_id that you can use to set up attachment placeholders.
By default, all recipients can see files attached by others. Setting visible_to_recipients to "false" ensures that only the envelope sender can access the attachment files provided by all signers.