For example, answering the question "what is this?" with an overly literal response.The word I am trying to remember would be used in the phrase "Not to be XXX but unexpected events are unexpected. That's why we didn't expect it." (The word isn't 'tautological' or 'redundant')
Vacuous: "having or showing a lack of thought or intelligence; mindless."
Your statement, "unexpected events are unexpected" might be called vacuously true if in a mathematics context.
I might go with trivial, which means "simple, transparent, or immediately evident" (sense 4b, here).
- "Not to be trivial, but unexpected events, are, well, unexpected."
But I don't think this captures your case of answering "What is this?" with an overly literal response.
An overly literal response would be 'pedantic'.
I would suggest axiomatic: