I hope to see more user-friendly help prompts and support for some language files!

[VIQingNiao]

The command help is only triggered when I intentionally enter an incorrect command, and it appears that this help text is available only in English and cannot be modified via the lang file.

To be honest, if this part of the content could be edited via a lang file and triggered by a new /help command, it would make this plugin much more user-friendly. I’ve seen another one of your very popular plugins, but I find it hard to understand why this one is so restrictive—it all seems a bit unreasonable. Of course, this is just my personal opinion. If you could improve it in the future by adding a /help command and allowing truly customizable messages, I’d still consider this plugin to be excellent. I wish you joy every day of your life!

Also, there’s a common issue with many of these inventory-checking plugins: when the player being checked has a large number of items with NBT data in their inventory, frequent queries can cause the server’s mspt value to rise, eventually leading to server lag. This is a common problem—I’m just mentioning it in case you have the time and energy to fix it. Of course, this is just a side note, and the impact isn’t that significant.

[Jikoo]

Hey, the inbuilt /help from Bukkit is fully customizable, so you can put whatever you like in there already. See https://docs.papermc.io/paper/reference/bukkit-help-configuration/
In terms of the topics from OpenInv that get added, Bukkit pulls those directly from command registrations, which aren't configurable via Bukkit because details are effectively fixed at compile time.

It looks like you're asking more specifically about the output of /openinv ? (or /openinv help, which has always bothered me because it means you can't open the player named "help" directly). The content is fetched from the same system, but wouldn't be super hard to change that. However, then we get into the messy area of "gee, should the parameters be configurable per-language too?" and the answer I've always come out with is that if some English comprehension is required to execute the command then it's acceptable (albeit a little annoying) if a bit more is required to understand the help.

Re: highly detailed items: Unfortunately, that's the tradeoff. The more information you stuff into a player's inventory, the more time it takes to read from disk. There are things you can do on the development side to offset that, such as storing only some form of hash/UUID in the item itself and then reading the rest of the data later as needed. If you're commenting regarding /searchinv and /searchender specifically, I'd ask that you make a separate issue for that, because while it is vaguely on my radar that I'd like to redo them (I had started about 5 years ago and got no feedback) it is not really recorded anywhere.