What is the Range of score values for XGBRanker predict method?

For example
preds = ranker.predict(X_test)
preds have ~2000 values and they are between -6.162417 and 5.1767716.

I am trying to figure out what is the min and max range score that XGBRanker can generate.
If there is no such range thing, how would someone put a threshold telling this are low ranked group, these are medium rank and these are high rank when deploying to prod?

The scores indicate the relative ordering among the items in X_test. There is no min and max range. You should order the items in X_test by the descending order of the scores and choose the top K items. (You may choose K suitably for your application.)

See Evaluating XGBoost Ranking for more information.

Thanks for the clarification.