Thank you (insert name here) for giving me the opportunity to review your (unnamed) work. Unfortunately I do not feel strongly enough about your (unnamed again) work to represent it effectively (or at all I should add). Initially this may be very disappointing to you.(really?) But remember this is just my subjective opinion. (on the unnamed work) Another agent could feel differently.  Let me reassure you that having an agent who is totally behind your work is (obviously we can cross the sender off that list) critical when trying to become a successful author. Best of luck with your writing career. Sincerely yours, blankety, blank blank

my comments are in orange