Debugging and performance clinic

The shortest debugging loop

1. Reproduce the problem in a fresh Test session.
2. Open Checks and select the source-linked diagnostic.
3. Change one component or behavior.
4. Test again before adding more content.
5. Keep a working cloud revision and publish only with zero error-level checks.

Use each diagnostic's Help link for the matching searchable error entry.

Controlled failure exercises

• Remove the player from a copy of a template, observe scene.player_missing, then undo.
• Move an entity past the world boundary, observe entity.outside_scene, then use the World panel and camera pan to place it intentionally.
• Add a Pickup without an Inventory component on the player, observe pickup.inventory_missing, then decide whether it should be a score collectible or inventory item.
• Add a sensor without a behavior, observe sensor.no_behavior, then attach controlled touch logic or select a purpose-built trigger component.

Publishing budgets

The current gate allows at most 2 MiB of project JSON, 20,000 entities, and 100,000 VM instructions, followed by a deterministic 120-tick simulation. These ceilings are safety limits, not targets. Prefer fewer meaningful entities, reuse prefabs, keep collision simple, and remove unreachable logic.