The list of criteria for where operations are appropriate used contains this bullet point.

• the intended purpose is to cause side effects such as the modification of existing resources or creation of new resources, or other changes out of scope of the RESTful interface (e.g. merging patient records)

Based on work group discussions I think many clinicians aren't familiar with the technical meaning of "side effects" from a computer science perspective. Recommend we add a note to clarify that merely creating a new Bundle resource and returning that to the client doesn't qualify as a side effect if that new Bundle isn't persisted on the server (server state hasn't changed).