How to Fix a Godot @tool Script Crashing on Null Nodes in the Editor

Adding @tool makes your script run inside the editor. Code that safely assumes nodes exist at runtime now hits nulls because the editor evaluates it before the scene is fully built.

How to fix it

1. Branch on editor hint

Wrap editor-only and runtime-only logic in if Engine.is_editor_hint(): checks so the editor never runs code that depends on a fully instantiated runtime tree.

2. Fetch nodes defensively

Use get_node_or_null() and test for null before touching children. In the editor the node may not be ready, so a hard get_node() will error.

3. Defer until ready

If you must access children, do it after NOTIFICATION_READY or wrap setup in if is_node_ready():, and call update_configuration_warnings() instead of crashing when something is missing.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every Godot error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.