without a clear plan or purpose and showing little effort or interest (Cambridge)
going from one thing to another, without a definite plan and without enthusiasm (Oxford)
He wandered around, cleaning up in a desultory way. (Cambridge)
She made a desultory attempt at conversation. (Cambridge)
Desultory attempt
Desultory conversation
Perfunctory
Cursory
Systematic
Structured
Desultorily