Engagement Invitation Verbage

I am having difficulty coming up with the appropriate verbage for an engagament invitation. I believe it should be simple and to the point without all of the "fluff" of a wedding invite. I also need to know how do you phrase a specific dress style on the invitation as well. The attire is coat and tie. How do you phrase it tactfully? Thanks for your help.
Posted by Jennifer; updated 06/21/04