code: def add_list_item(list_id, options={})
        response = connection.post do |req|
          req.url "lists/#{list_id}/additem", options
        end
          return_error_or_body(response, response.body.response.item)
      end
docs: Add an item to a list: https://developer.foursquare.com/docs/lists/additem
  
   @param [String] list_id - The id of the list to update
   @param [Hash] options (all optional)
   @option options String :venueId - A venue to add to the list.
   @option options String :text - text to add to item
   @option options String :url - associate a url with the tip
   @option options String :tipId - Used to add a tip to a list
   @option options String :listId - Used with itemId to copy item from a list
   @option options String :itemId - Used with listId to copy item from a list