Feature description
From the corresponding paper Simola et al. 2021 https://projecteuclid.org/journals/bayesian-analysis/volume-16/issue-2/Adaptive-Approximate-Bayesian-Computation-Tolerance-Selection/10.1214/20-BA1211.full

Motivation/Application
Adaptive quantile selection, with promising results reported in the paper.

Difficulty
Not too difficult, just may require some additional information to be recorded and passed to the Epsilon class.