anchor.diff:    }
   
     /**
  -  * @hint This endpoint allows you to retrieve all custom fields.
  +  * @hint Retrieve all custom fields.
     */
     public struct function listCustomFields() {
       return apiCall( 'GET', "/contactdb/custom_fields" );
     }
   
     /**
  -  * @hint This endpoint allows you to retrieve a custom field by ID.
  +  * @hint Retrieve a custom field by ID.
     */
     public struct function getCustomField( required numeric id ) {
       return apiCall( 'GET', "/contactdb/custom_fields/#id#" );
     }
   
     /**
  -  * @hint This endpoint allows you to delete a custom field by ID.
  +  * @hint Delete a custom field by ID.
     */
     public struct function deleteCustomField( required numeric id ) {
       return apiCall( 'DELETE', "/contactdb/custom_fields/#id#" );
     }
   
     /**
  -  * @hint This endpoint allows you to list all fields that are reserved and can't be used for custom field names.
  +  * @hint List all fields that are reserved and can't be used for custom field names.
     */
     public struct function listReservedFields() {
       return apiCall( 'GET', "/contactdb/reserved_fields" );
  
positive.code: 
    /**
    * https://sendgrid.api-docs.io/v3.0/contacts-api-lists/retrieve-all-lists
    * @hint This endpoint allows you to retrieve all of your recipient lists. If you don't have any lists, an empty array will be returned.
    */
    public struct function listLists() {
      return apiCall( 'GET', '/contactdb/lists' );
  
negative.code: 
    /**
    * https://sendgrid.api-docs.io/v3.0/contacts-api-lists/add-multiple-recipients-to-a-list
    * @hint Add multiple recipients to a list.
    * @recipients an array of recipient IDs or email addresses
    */
    public struct function addRecipientsToList( required numeric listId, required array recipients ) {
      var recipientIds = recipients;
  
      if ( recipients.len() && isValid( 'email', recipients[1] ) ) {
        recipientIds = recipients.map(
          function( item, index ) {
            return returnRecipientId( item );
  