@KillerBean @tek i do this sometimes by replying Am I expected to provide a deliverable for this meeting? Or, am I being consulted or informed?
If you can tell me what you need via email, I'll use the meeting time as a working session on my calendar to produce the deliverable. (A report, etc...)
If I'm being consulted, please provide any foundational information and documentation so i can knowledgeably assist. Along with any direct questions.
If being informed, please provide the following in one to two sentences each.
What is happening?
Why is it happening?
When is it happening?
What should I do?
This is usually enough to convey that I'm not attending nonsense meetings when I could be learning, or building cool stuff, or solving Ops issues, etc...