This article describes an engineering process representation and modeling t
ool. The approach is especially suitable for describing large-scale, mature
design processes involving numerous tasks, same of which may be performed
by automated computer agents. The underlying representation is a graph of i
nformation-processing units with explicitly defined input and output featur
e elements. We show that this representation is more complete than those us
ed in previous process modeling approaches and overcomes some of their limi
tations when dealing with design processes involving dependencies at multip
le levels of detail. The representation is combined with rules for automati
cally operating upon the graph to preserve consistency when traversing to h
igher or lower levels of detail.