I know the operator wg has been working on a definition. For my own thought process I wrote down my thinking in a doc. You can find that doc at https://docs.google.com/document/d/13qHfdHwniZBaLpDClcGaWTk6kTbaU7j7hWQFj-a1cgY/edit?usp=sharing

It outlines a definition (based on the CoreOS one but removing the requirement for the thing being stateful), pulls out and highlights the key points with descriptions, and provides some examples to test it.

Because this was for my own thought process and it's rather long (2.5 pages), I did not put this into the operator definition working doc.

Thoughts and feedback welcome.

- Matt Farina