For AI agents

This page is for language models (and the people pointing them here). It says where to find everything and the rules a Myriad addon has to follow. Read it first.

Reading these docs

• /llms.txt lists every page with a summary. /llms-full.txt is all of them in one file. Every page is also plain Markdown at its address plus .md: /docs/develop/hooks.md.
• The API’s javadoc ships with dev.myriadclient:myriad (-sources.jar and -javadoc.jar on https://maven.myriadclient.dev/releases). Every public class and method is documented: read it when these pages don’t cover a detail.
• Working code to copy patterns from: the addon template , the example addon , and Essentials .

What to build, in order

1. Start from the template; rename the mod id, package and main class (Setting up).
2. Write modules: Modules, Settings, Events.
3. Act through Services, never raw packets, when a service covers it.
4. Add windows and HUD elements if needed (UI), commands (Commands).
5. Only if the task is to change how Myriad or another addon decides something: Hooks.
6. Build with ./gradlew build; test with the dev client and selftest (Testing).

Rules

These are not style preferences. An addon that breaks them breaks for players.

1. Only import dev.myriadclient.api.*. Never dev.myriadclient.impl.*: it’s internal and changes every release.
2. Never implement an interface marked @ApiStatus.NonExtendable (services, AddonContext, Window, Canvas, Hooks…). To replace a service, extend its Forwarding class.
3. Register everything in MyriadAddon.initialize through the AddonContext. Categories in registerCategories. Optional integrations in postInitialize.
4. No static instances or static state. Shared state is an object made in initialize and passed to constructors. Reach a module with Modules.active(MyModule.class) (null while off).
5. Act in TickEvent.Pre (clicks, placing, breaking, attacking, slot switches), or through a service that does.
6. Rotate through Myriad.rotations(), switch slots through Myriad.inventory(), place through Myriad.placement(), break through Myriad.breaking(). Pass this (the module) as the owner.
7. Use Options.forServer() for services’ options. Don’t add a “Strict”/“Grim” setting.
8. Settings come from groups (sgGeneral.bool("Name")...build()), with a description. Colours default to theme roles (SettingColor.role(SettingColor.Mode.ACCENT)).
9. .protect() every private setting: URLs with tokens, webhooks, passwords, coordinates, server addresses, file paths, free text that could hold them.
10. Never write another module’s settings to change its behaviour. Lay an override (setting.override(this, Setting.Layer.MODULE, "Label", value)) and release(this) when done.
11. Don’t depend on Essentials at runtime. To use its hooks, compileOnly it and register behind FabricLoader.getInstance().isModLoaded("myriad-essentials"), in a separate class.
12. Mixins stay thin: they call a method on the module, which checks Modules.active(...). Prefix handler names with the mod id. Prefer an event when one exists.
13. Hooks are for decisions: use ctx.hook(...) only to answer a decision; call call.proceed() when you have no answer; scope with the narrowest Match. A replacement scoped to your addon hands calls on with super.
14. Ticks are cheap, frames are not: keep render handlers light; cache per tick (TickCached) or per chunk (ChunkCache).
15. Keep the jar’s fabric.mod.json correct: entrypoints.myriad, depends.myriad (the oldest supported), environment: client, contact.sources for updates.

Common mistakes

A complete, correct module

package com.example.addon.modules;
 
import dev.myriadclient.api.Myriad;
import dev.myriadclient.api.combat.TargetSettings;
import dev.myriadclient.api.combat.Targets;
import dev.myriadclient.api.event.Subscribe;
import dev.myriadclient.api.event.events.TickEvent;
import dev.myriadclient.api.module.Categories;
import dev.myriadclient.api.module.Module;
import dev.myriadclient.api.service.Rotations;
import dev.myriadclient.api.setting.DoubleSetting;
import dev.myriadclient.api.util.Interactions;
import net.minecraft.world.entity.Entity;
 
/** Faces the nearest target in range and hits it when the attack is charged. */
public final class SimpleAura extends Module {
    private final DoubleSetting range = sgGeneral.doubleSetting("Range")
        .description("How far to reach for a target.")
        .defaultValue(3.0).range(1, 6).decimals(1)
        .build();
    private final TargetSettings targets = new TargetSettings(settings, Targets.Type.PLAYERS, Targets.Type.HOSTILES);
 
    public SimpleAura() {
        super(Categories.COMBAT, "Simple Aura", "Hits the nearest target in range.");
    }
 
    @Subscribe(inGame = true)
    private void onTick(TickEvent.Pre e) {
        Entity target = targets.best(range.get());
        if (target == null) return;
        float[] aim = Myriad.rotations().anglesTo(target.getBoundingBox().getCenter());
        Myriad.rotations().request(this, aim[0], aim[1], Rotations.PRIORITY_NORMAL, Rotations.Options.forServer(), null);
        // Hit once the server faces it and the attack is charged (Interactions.attack also swings).
        if (Myriad.inventory().attackCharge() >= 1 && Myriad.rotations().isFacing(aim[0], aim[1], 15)) {
            Interactions.attack(target, true);
        }
    }
}