Opening a full 3D application to answer "is this file any good" is slow. Most of the questions have faster answers.
What to check, in order
- Does it open at all? Corrupt or truncated files are common in transfer.
- Scale. Compare against a known reference. Wrong units are the single most common problem.
- Triangle count. Against your budget for that asset's role.
- Materials and textures. Are they embedded, referenced, or missing entirely? A GLB embeds; an OBJ references a separate MTL and image files that may not have travelled with it.
- UVs. Is there a layout, and is it sane? Overlapping or absent UVs cap what you can do later.
- Normals. Flipped faces show as black or inside-out surfaces.
- Pivot and orientation. Where is the origin, and which way is up?
- Rigging. If it should have a skeleton, does it, and are the bone names sensible?
Lightweight ways to look
Browser-based glTF viewers handle GLB well and show materials, animations and statistics without installing anything. Most operating systems preview common formats natively. Engine content browsers show import-time statistics before you commit the asset.
The wireframe and normals check
Two overlays answer most quality questions at a glance. Wireframe shows whether topology is machine-made or authored. Face-orientation shading shows flipped normals immediately, and flipped normals are the defect most likely to be missed until it renders wrong.
For generated models
Expect: dense uniform topology, a single material, a base colour texture, arbitrary scale, a bounding-box pivot, and no skeleton. That is the normal state of a fresh reconstruction rather than a fault — the checklist above is what turns it into a specification for the cleanup work.