reesIdeal(..., Trim => true)Note that when Trim=>true, the generators used will be the ones (and in the order) M2 likes, possibly not the original ones.
The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/ReesAlgebra.m2:854:0.