Simple script to check quickly the existing contact info:
tell application id "com.apple.AddressBook" to set thePeople to name of people
set theChoice to choose from list thePeople
if theChoice is false then return
tell application id "com.apple.AddressBook"
close windows
set selectedContact to person named (item 1 of theChoice)
tell selectedContact
set {|birth date|, |company|, |creation date|, |department|, |first name|} to ¬
{birth date, company, creation date, department, first name}
set {|home page|, |id|, |job title|, |last name|, |maiden name|} to ¬
{home page, id, job title, last name, maiden name}
set {|middle name|, |modification date|, |name|, |nickname|, |note|, |organization|} to ¬
{middle name, modification date, name, nickname, note, organization}
set {|phonetic first name|, |phonetic last name|, |phonetic middle name|} to ¬
{phonetic first name, phonetic last name, phonetic middle name}
set {|selected|, |suffix|, |title|, |vcard|} to {selected, suffix, title, vcard}
set |1st Phone Number| to value of phone 1
end tell
end tell
tell application "System Events" to open location "addressbook://" & |id|
set theText to "Creation date: " & |creation date| & return
set theText to theText & "Modification date: " & |modification date| & return
if not (|1st Phone Number| is missing value) then set theText to "1st Phone number: " & |1st phone Number| & return
if not (|birth date| is missing value) then set theText to "Birth date: " & |birth date| & return
set theText to theText & "Company: " & company & return
if not (department is missing value) then set theText to theText & "Department: " & department & return
if not (|first name| is missing value) then set theText to theText & "First name: " & |first name| & return
if not (|home page| is missing value) then set theText to theText & "Home page: " & |home page| & return
if not (|job title| is missing value) then set theText to theText & "Job title: " & |job title| & return
if not (|last name| is missing value) then set theText to theText & "Last name: " & |last name| & return
if not (|maiden name| is missing value) then set theText to theText & "Maiden name: " & |maiden name| & return
if not (|middle name| is missing value) then set theText to theText & "Middle name: " & |middle name| & return
if not (|name| is missing value) then set theText to theText & "Name: " & |name| & return
if not (nickname is missing value) then set theText to theText & "Nickname: " & nickname & return
if not (|note| is missing value) then set theText to theText & "Note: " & |note| & return
if not (organization is missing value) then set theText to theText & "Organization: " & organization & return
if not (|phonetic first name| is missing value) then set theText to theText & "Phonetic first name: " & |phonetic first name| & return
if not (|phonetic last name| is missing value) then set theText to theText & "Phonetic last name: " & |phonetic last name| & return
if not (|phonetic middle name| is missing value) then set theText to theText & "Phonetic middle name: " & |phonetic middle name| & return
set theText to theText & "ID: " & |id| & return
set theText to theText & "Selected: " & selected & return
if not (suffix is missing value) then set theText to theText & "Suffix: " & suffix & return
if not (title is "") then set theText to theText & "Title: " & title
set theText to theText & return
tell application id "com.apple.AddressBook"
display dialog theText buttons {" ...........................------------------- CLOSE INFO --------------------- ............................."} with title "CONTACT's INFO"
quit it
end tell
return theText & vcard