Stack mismatched objects in a stable order

The prompt

Here we have a book, 9 eggs, a laptop, a bottle and a nail. Please tell me how to stack them onto each other in a stable manner.

Expected result

A stacking order reasoned from real-world physical properties — book on the bottom as the flattest base, then laptop, bottle, eggs nested carefully, nail balanced last — with the model explaining why that order is stable.

Why it works

Tests whether a model reasons about real physical constraints (weight, flatness, fragility) instead of pattern-matching a generic answer — a quick sanity check before trusting a model with anything requiring spatial or physical common sense.