Is there a standard list of criteria that we need to validate before we can, say, "consider" a particular epic for an iteration. I was referring to maybe a checklist or a set of questions that we need to ask ourselves / product owner.
BACKGROUND: I am trying to set up a Agile process which will not be individual dependent and hence the need for a checklist.
Almost by definition, an "epic" is simply a placeholder for some desired functionality. It contains very little detail and so, would not be considered for an iteration.
The "epic" needs to be broken down into smaller product backlog items that do contain enough detail, are therefore estimatable and are small enough that they can be completed within an iteration. (In fact, I usually recommend teams I work with make product backlog items small enough that between 5 and 15 can be taken into a sprint).