Add PAI Display Name to an Invite response (18x) based on UA value in Invite Request

HI all,

Looking for some help.

I have built an HMR to add a uri "Display Name" to the PAI header of any Invite responses that don't have a uri-display populated, this works well enough in my lab.

        header-rule

                name                                    PAIDisplayName

                header-name                             p-asserted-identity

                action                                  manipulate

                comparison-type                         pattern-rule

                msg-type                                reply

                methods                                 Invite

                match-value                            

                new-value                              

                element-rule

                        name                                    Add_Dummy_Display_Name

                        parameter-name                         

                        type                                    uri-display

                        action                                  add

                        match-val-type                          any

                        comparison-type                         pattern-rule

                        match-value                             ^$

                        new-value                               "\"External\""

I now wish to be specific about the responses that this rule is applied to instead of catching all.

My idea is to match the  content of the  "User-Agent" header in the corresponding Invite request and only apply the header/element rule above based on this.