Using AI assistants well

AI chat assistants can write plugin code in seconds, and much of it is wrong in ways that are easy to miss. On this page you will learn how to ask for code that fits Paper 26.3, how to spot out-of-date code, how to check a result before it touches your server, and how to use an assistant to learn instead of just copy.

What an AI assistant is good and bad at

An AI assistant is a program that has read an enormous amount of text, including millions of lines of Minecraft plugin code, and writes new text that looks like what it read. It is useful and fast. It can explain a line, suggest a structure, write a first draft, and translate an error message into plain words.

It also has two weaknesses that matter a lot for plugins:

• It learned from old code. Most plugin code on the internet is years old. Minecraft and Paper change every year, so the assistant often writes the way plugins were written in 2019.
• It sounds sure when it is wrong. It can invent a method that does not exist and explain it like it does, and nothing in the answer warns you.

The good news: you can test almost everything, and this guide gave you the tools. The rest of this page is about doing that.

Tell it your versions every time

The single most useful habit is to start each new chat with a short block that describes your setup. Keep it in a text file and paste it first:

1I am a beginner writing a Paper plugin.12- Minecraft and Paper 26.3 (API io.papermc.paper:paper-api:26.3.build.142-beta)3- Java 254- Gradle with Kotlin DSL (build.gradle.kts), plugin.yml with api-version '26.3'25- Use the modern API only: Adventure Components or MiniMessage for text,6  Brigadier or BasicCommand for commands, no deprecated methods.37- No NMS or CraftBukkit imports unless I ask for them.48- Explain every new class or method you use in one short sentence.

Good prompts

A prompt is the message you send. The more precise it is, the better the code. Compare these two:

1make a heal plugin

1Write a /fullheal command for my Paper 26.3 plugin.12Behavior:3- Only players can use it. The console gets a red message.4- It needs the permission aifixed.fullheal.5- The player is healed to full health after 3 seconds, not right away.26- If the player left the server in those 3 seconds, do nothing.37Constraints: Java 25, no deprecated API, no waiting on the main thread.8Give me the files I need and tell me what goes in plugin.yml.

Here are three prompt shapes that cover most of what you will do. Pick the one that fits:

Red flags in generated code

Here is what an assistant that has not been told your versions might write for the strong prompt above. It looks reasonable. Read it once, then look at the notes. A word you will see a lot is deprecated: the authors have marked a method as old, and it may be removed. Every example in this guide is compiled with deprecation warnings treated as errors, so you only see current code here.

1public class HealPlugin extends JavaPlugin implements Listener {2 3    public void onEnable() {4        getServer().getPluginManager().registerEvents(this, this);15        getCommand("fullheal").setExecutor(this);6    }7 8    @EventHandler29    public void onChat(AsyncPlayerChatEvent event) {10        if (event.getMessage().equalsIgnoreCase("help")) {311            event.getPlayer().sendMessage(ChatColor.GREEN + "Try /fullheal");12        }13    }14 15    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {416        Player player = (Player) sender;17        player.sendMessage("Healing in 3 seconds...");18        try {519            Thread.sleep(3000);20        } catch (InterruptedException exception) {21        }622        player.setHealth(player.getAttribute(Attribute.GENERIC_MAX_HEALTH).getValue());23        return true;24    }25}

One answer, seven problems. Keep this table: it covers the most common red flags you will see in generated code.

Here is the same plugin after checking it against the table. It is a real project that compiles on Paper 26.3. Compare it with the "bad" version line by line:

1package com.example.aiassistantsfixed;2 13import io.papermc.paper.event.player.AsyncChatEvent;24import net.kyori.adventure.text.serializer.plain.PlainTextComponentSerializer;5import org.bukkit.event.EventHandler;6import org.bukkit.event.Listener;7 8public final class HelpChatListener implements Listener {9 10    @EventHandler11    public void onChat(AsyncChatEvent event) {12        String message = PlainTextComponentSerializer.plainText().serialize(event.message());313        if (message.equalsIgnoreCase("help")) {414            event.getPlayer().sendRichMessage("<green>Try <yellow>/fullheal</yellow> to restore your health.");15        }16    }17}

1package com.example.aiassistantsfixed;2 3import io.papermc.paper.command.brigadier.BasicCommand;4import io.papermc.paper.command.brigadier.CommandSourceStack;5import org.bukkit.attribute.Attribute;6import org.bukkit.attribute.AttributeInstance;7import org.bukkit.entity.Player;8import org.bukkit.plugin.Plugin;9 110public final class FullHealCommand implements BasicCommand {11 212    private static final long THREE_SECONDS_IN_TICKS = 60L;13 14    private final Plugin plugin;15 16    public FullHealCommand(Plugin plugin) {17        this.plugin = plugin;18    }19 20    @Override21    public void execute(CommandSourceStack source, String[] args) {322        if (!(source.getSender() instanceof Player player)) {23            source.getSender().sendRichMessage("<red>Only players can use this command.");24            return;25        }26        player.sendRichMessage("<gray>Healing in 3 seconds...");427        plugin.getServer().getScheduler().runTaskLater(plugin, () -> heal(player), THREE_SECONDS_IN_TICKS);28    }29 30    private void heal(Player player) {731        AttributeInstance maxHealth = player.getAttribute(Attribute.MAX_HEALTH);532        if (!player.isOnline() || maxHealth == null) {33            return;34        }35        player.setHealth(maxHealth.getValue());36        player.sendRichMessage("<green>You feel much better.");37    }38 39    @Override840    public String permission() {41        return "aifixed.fullheal";42    }43}

1package com.example.aiassistantsfixed;2 3import java.util.List;4import org.bukkit.plugin.java.JavaPlugin;5 6public final class AiFixedPlugin extends JavaPlugin {7 8    @Override9    public void onEnable() {110        getServer().getPluginManager().registerEvents(new HelpChatListener(), this);211        registerCommand("fullheal", "Restores your health after three seconds", List.of(), new FullHealCommand(this));12    }13}

Check AI code before you trust it

Use the same routine for every piece of generated code, even when it looks perfect:

1. Commit first

   Before you paste new code into your project, commit what you have (see Git and GitHub). If the AI's change makes things worse, one click returns you to the working version.

2. Read it, top to bottom

   You do not have to understand everything yet. You do need to find every class and method name you do not recognize. Those are the places where it may be invented or outdated.

3. Compile it

   Paste the code into the Compile Lab, or into IntelliJ, and build. Red names and compile errors are very often the assistant using something that does not exist in 26.3. Paste the exact error back to the assistant.

4. Explain it to yourself

   Put the code in the Code Explainer, or ask the assistant to explain every line. If an answer does not make sense, ask again. Never run code you cannot describe in your own words.

5. Run it and try to break it

   Start your test server (Test Server) and use the feature the way a player would. Then use it the way a careless player would: from the console, with no arguments, with a name that does not exist, while another player watches. These are the cases AI skips.

Never paste secrets, and mind licenses

An AI chat is a website run by a company. Treat anything you type as something that could be stored or seen by someone else. So never paste:

• Passwords, API keys, tokens, Discord webhook addresses, database logins (see the secrets section). Replace them first with FAKE_TOKEN.
• The IP addresses and private details of your players, for example from log files.
• Code that belongs to someone else and is not yours to share, such as a paid plugin's source.

Licenses work the other way too. Code an assistant writes can still look a lot like code from a public project, and open source licenses (see Releasing and sharing your plugin) have rules. A few habits keep you safe: do not ask it to copy a named plugin; understand and rewrite what you use; and when you publish, you are responsible for everything in your jar.

The learning loop

You are here to learn to write plugins, not just to collect plugin code. Assistants can help with that, if you use them as a tutor and not a vending machine.

• Ask why. "Why is runTaskLater better than Thread.sleep?" A good answer makes you stronger, and a vague one tells you to check the docs.
• Rewrite it yourself. After you understand the code, close the chat and type the feature again from memory in a new file. When you get stuck, look back at only the part you forgot.
• Ask for alternatives. "Show two other ways to do this and when I would choose each."
• Ask to be quizzed. "Ask me three questions about this code, one at a time, and wait for my answers."
• Change one thing at a time. Change the delay or the message and predict what will happen before you run it.

A useful rule of thumb: if you could not explain a piece of code to a friend, it is not yours yet. Keep going until it is.

Mistakes to avoid

• Pasting a whole project and saying "fix it". Send the one file and the one error.
• Skipping the versions. This single mistake causes most of the old code you will get.
• Trusting a method name because it sounds right. Look it up in the API map or autocomplete.
• Running generated code on your real server first. Always test locally.
• Letting the assistant write everything. You will end up with a plugin you cannot fix.

1@EventHandler2public void onJoin(PlayerJoinEvent event) {3    Player player = event.getPlayer();4    player.sendMessage("§aWelcome " + player.getName());5    player.setDisplayName("§6" + player.getName());6    Thread.sleep(2000);7    player.sendMessage("§7Read the rules with /rules");8}

1Setup: Paper 26.3, Java 25, Gradle Kotlin DSL, modern API only (Components, BasicCommand or Brigadier,2no deprecated methods, no NMS). Explain each new method in one sentence.3 4Write a /spawn command.5- Only players can use it. Others get a red message.6- When used, the player sees "Teleporting in 5..." and the number counts down each second.7- At 0 they teleport to their world's spawn location.8- If they move to a different block during the countdown, cancel it and tell them.9- If they run /spawn again while counting down, tell them it is already running.10- Never block the main thread.11Give me the files and the plugin.yml.

Recap

• Assistants write fast, but from old examples and with great confidence. Test everything.
• Start each chat with your versions: Paper 26.3, Java 25, Gradle Kotlin DSL, modern API.
• Good prompts describe behavior, edge cases and constraints, and include your current code and the exact error.
• Red flags: ChatColor, AsyncPlayerChatEvent, getCommand with a Paper plugin file, GENERIC_MAX_HEALTH, needless NMS, Thread.sleep, blocking work on the main thread.
• Check: commit, read, compile, explain, run and try to break it.
• Never paste secrets or private data. Respect licenses.
• Ask why, then rewrite it yourself, so the knowledge becomes yours.

Quick quiz

Next steps

• Where to go next: official docs, communities, and a ladder of project ideas.
• Compile Lab and Code Explainer: the two tools used in the check routine.
• Common errors: look up an error message before you ask anyone.