Read contacts
Usecollection_query to read a small page of contact records. Follow the returned cursor before treating the result as complete.
Update a contact
Usecrm_record to update a contact that already exists:
File a person
Usepeople_file to save a person who has already been revealed or imported into the appropriate contact collection.
A contact lookup, filing the contact, and updating the contact are separate actions. Each one can have a different permission or confirmation requirement.
