[rules-dev] Why are fundamental API functions not part of "stable"?

[Wolfgang Laun]

Trying to provide some debugging functions, I find that
org.drools.runtime.rule.WorkingMemory (a "stable" interface) lets you retrieve
org.drools.runtime.rule.Agenda (another "stable" interface). But this
one does not provide access to the current set of Activation objects.

In contrast to this, org.drools.Agenda, which is part of the
"unstable" Core API, does provide Activation[] getActivations().

Since there is org.drools.runtime.rule.Activation in the "stable"
part, why is it not possible to retrieve the current activations by
just using the "stable" API? I would think that concepts such as
"agenda" and its current set of activations are here to stay. What
should one do when one wants to implement support functions for Drools
applications that should have long term stability??

Best
Wolfgang