"Child '...' contains invalid value"

Server log

[ERROR]: Permission node 'myplugin.all' in plugin description file for MyPlugin v1.0 is invalid
java.lang.IllegalArgumentException: Child 'myplugin.use' contains invalid value

What it means

Each child under children must be true or false. If one is not, the server skips the whole parent permission. The plugin still loads.

What causes it

Usually true written in quotes, which makes it text instead of a yes/no value.

How to fix it

Before

permissions:
  myplugin.all:
    children:
      myplugin.use: 'true'

After

permissions:
  myplugin.all:
    children:
      myplugin.use: true

The message "'children' key is of wrong type" is related: it means children itself is plain text instead of a list or a section, for example children: myplugin.use. Write children: [myplugin.use].

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