What exactly IS existentialist literature

Okay everybody don’t hate me i come in peace with my arms in the air. I am quite well read in existentialist literature and am somewhat acquainted with philosophy and the teachings within it.

Be that as it may i can’t for the life of me DEFINE existentialist literature or existentialism with a view of creative writing and literary texts.

From what I’ve learned: existentialism is the concept of having complete autonomy of one’s actions (as “complete” as possible anyway), and thus having full responsibility and accountability as far as consequences go— seeing as they are the sole drivers of their choice and actions.

So what is existentialism when it comes to literature?

WHAT IS EXISTENTIALIST LITERATURE??!!😭😭😭