How to provision SCIM2.0 Complex attribute like Manager

The manager is part of the extended schema, so needs to be in a “container” for that schema. Then, all you need to provide is the id of the manager as the value:

{
    "urn:ietf:params:scim:schemas:sailpoint:1.0:User": {},
    "emails": [
        {
            "type": "work",
            "value": "[email protected]",
            "primary": "true"
        }
    ],
    "schemas": [
        "urn:ietf:params:scim:schemas:sailpoint:1.0:User",
        "urn:ietf:params:scim:schemas:core:2.0:User",
        "urn:ietf:params:scim:schemas:extension:enterprise:2.0:User"
    ],
    "name": {
        "formatted": "Andrew.Dwyer",
        "familyName": "Dwyer",
        "givenName": "Andrew"
    },
    "active": true,
    "userName": "Andrew.Dwyer",
    "password": "xyzzy",
    "urn:ietf:params:scim:schemas:extension:enterprise:2.0:User": {
        "department": "Finance",
        "manager": {
            "value": "7bac06aaf46811ebaea21bb0add92936"
        }
    }
}