Open APIs

I am trying to correctly embed contact medium information directly in the create product order (with external consumers, calling first TMF632 is a bit annoying).
The below construction seems to be a valid approach (using the extension in TMF632).
However it seems in the model we can only use the PartyRole at product level on the order item. On the order level you can apparently only use PartyRoleRef, not PartyRole.
Is this correct? If so, is there some reason for this difference?

"relatedParty": [
          {
            "@type": "RelatedPartyOrPartyRole",
            "role": "customerContact",
            "partyOrPartyRole": {
              "@type": "PartyRole",
              "name": "Customer Contact Role",
              "role": "customerContact",
              "engagedParty": {
                "@type": "PartyRef",
                "id": "474730717",
                "name": "Sam Smith"
              },
              "contactMedium": [
                {
                  "@type": "ContactMedium",
                  "contactType": "telephone",
                  "preferred": true,
                  "@schemaLocation": "https://tmforum.org/TMF632/PartyManagement/PhoneContactMedium.schema.json",
                  "phoneNumber": "0032467384756"
                },
                {
                  "@type": "ContactMedium",
                  "contactType": "email",
                  "preferred": false,
                  "@schemaLocation": "https://tmforum.org/TMF632/PartyManagement/EmailContactMedium.schema.json",
                  "emailAddress": "Sam.Smith@ispX.com"
                               }
              ]
            }
          }
        ]
      

Note: on the TMF621 trouble ticket API I don't see either a way to use PartyRole, only PartyRoleRef.
( With API calls coming from the external world it is rather complex to force 3rd parties to first use TMF632 to create contacts with an ID...)
You can of course solve things with the v5 characteristic model, but that does not sound like a good modelling approach...

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Peter Broucke
Proximus SA
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