tossed off

ad hoc ad lib at first glance automatic by ear casual expedient extempore free immediate impromptu improv improvisatory improviso informal jamming made-up makeshift off the cuff off the top of head offhand on impulse on-the-spot snap spontaneous spur-of-the-moment taking for ride thought out loud tossed out unplanned unpremeditated unprepared unstudied winging it

planned prepared read rehearsed written

offhand spontaneous unscripted

ad-lib fake

dashed off extemporaneous extempore extemporized faked improv improviso off the cuff played by ear shot from the hip spur-of-the-moment thrown off unpremeditated unprepared unstudied vamped whipped up winged

deliberate planned