Minecraft Version

1.21.1

KubeJS Version

2101.7.2-47386b6

Rhino Version

2101.2.7-b74

Architectury Version

13.0.8

Forge/Fabric Version

NeoForge 21.1.132

Describe your issue

KubeJS doesn't seem to know what neoforge:never is

Crash report/logs

No response

Those are the 1.21.4 versions of the docs, you are using 1.21.1 and the docs can be found here: https://docs.neoforged.net/docs/1.21.1/resources/server/conditions
Where it uses true and false instead of never and always.

using it by itself seems to work fine

maybe it's just that the file is empty otherwise