Bounds are raw HP, not a percentage: 50 means 50 health points, not
50%. A full-health player is at 100 unless something raised their max
health.
Either bound can be null (or omitted entirely) for “no limit on that
side”, but at least one bound is required. A condition with neither
bound would always be satisfied, so it is invalid and the contract will not
load.
Set only maxHealth for a “while wounded” rule, or only minHealth for a
“while healthy” rule.
If minHealth is greater than maxHealth, the plugin swaps them and logs
a warning.
Configs from before 1.8.0 used -1 to disable a bound. The plugin still
reads a negative bound as “no bound”, and importing an old file into the
editor rewrites it to null automatically.