Single-file CLI that writes a "sanity card" for a crystal structure before any model interprets it: minimum pair distance, fine symmetry-tolerance sweep, coordination fingerprint, bond statistics, reference-structure displacement (spglib refine_cell), and an optional declared-prototype gate (--prototype rocksalt|cesium_chloride|zincblende|fluorite|spinel) that catches species label swaps invisible to geometry and bond valence sums. Prototype templates are built from ASE's Wyckoff tables, independent of pymatgen's generators, after the origin-choice scar documented in the accompanying post series. Usage: python structure_sanity_card.py structure.cif --output card.md [--json report.json] [--prototype spinel]. Dependencies: pymatgen, numpy, spglib; gate adds scipy + ase.