For example, you type "/help", you can see some incomplete usage of commands such as:
- advancement (grant|revoke)
- effect (clear|give)
- should be "effect clear [<target>] [<effect>]" and "effect give <target> <effect> <duration> <level> [true|false]"
- summon <entity> [<pos>]
- should be "summon <entity> [<pos>] [<data>]
- time (add|set|query)
- should be "time (add|set) <value>" and "time query (day|daytime|gametime)"