| UUID | uuid | string | | Universally Unique Identifier. |
| Label | label | string | | Label for the inbox. |
| Key | key | cbc.Key | | Type of inbox being defined if required for clarification between multiple inboxes. |
| Scheme | scheme | cbc.Code | | Scheme ID of the code used to identify the inbox. This is context specific and usually an ISO 6523 code or CEF (Connecting Europe Facility) code. |
| Code | code | cbc.Code | | Code or ID that identifies the Inbox. Mutually exclusive with URL and Email. |
| URL | url | string | | URL of the inbox that includes the protocol, server, and path. May be used instead of the Code to identify the inbox. Mutually exclusive with Code and Email. |
| Email | email | string | | Email address for the inbox. Mutually exclusive with Code and URL. |
