Indicate which fields to return in the response, separated by commas. Supported fields are:
- fsq_tip_id - The ID of the tip to be returned.
- created_at - The timestamp indicating when the tip was created; UNIX timestamp in seconds since Epoch.
- text - The text of the returned tip.
- lang - The language of the returned tip.
- url - The URL associated with the returned tip.
- agree_count - The count of users who have agreed with the returned tip.
- disagree_count - The count of users who have disagreed with the returned tip.
- photo - The ID of the photo asociated with the returned tip.
Default fields if this param is omitted are "fsq_tip_id", "created_at", and "text".