A summarist is someone who writes a short version of something, like a story or a report.
A summarist is helpful because they make things easier to understand.
Examples:
The summarist wrote a short version of the book.
I want to be a summarist when I grow up.
The summarist made the long story into a short one.
The summarist helps people understand things better.
The summarist can make a big story very small.
The summarist's job is to make things easy to understand.