A container is a fully 3D box — length, width, AND height must accept the item simultaneously; corner reachability is a soft second constraint.
- Treat the container as a 3D box and generate the item’s 6 dimension permutations (3 axes × 2 flips).
- For each permutation, apply the constraint: item ≤ container on length, width, and height simultaneously.
- Check reachability — items longer than arm’s reach can’t be loaded all the way into the back corners.
- Subtract 1.5 in handling clearance on each axis for the mover’s grip plus pivot room.
- Verdict ladder (verdict-tiers.js, shared with door): FITS ≥ 2 in; FITS_TIGHT 0.5–2 in; FITS_VERY_TIGHT 0–0.5 in; DOESN'T_FIT below.
Interior dimensions use the published spec; door rails, ribs, and floor lashings can shave 1–2 in off the usable corners.