minecraft-modding
Minecraft Modding Skill
Overview
This skill guides Codex through developing open-source Minecraft mods. Target platforms:
| Platform | MC Version | Java | Build System |
|---|---|---|---|
| NeoForge | 1.21.x with 1.21.11 examples | Java 21 | Gradle + ModDevGradle |
| Fabric | 1.21.x with 1.21.11 examples | Java 21 | Gradle + Fabric Loom |
| Architectury (multiloader) | 1.21.x | Java 21 | Gradle + Architectury Loom |
Always confirm the platform and Minecraft version from gradle.properties or build.gradle
before writing any mod-specific code.
Routing Boundaries
Use when: the task is Java/Kotlin mod code, registry/event work, networking, datagen wiring, and loader APIs.Do not use when: the task is command-only vanilla logic (minecraft-commands-scripting) or pure datapacks (minecraft-datapack).
More from jahrome907/minecraft-codex-skills
minecraft-testing
Write automated tests for Minecraft mods and plugins for 1.21.x. Covers NeoForge GameTests (@GameTest annotation, GameTestHelper assertions, test structure placement), Fabric game tests (fabric-gametest-api-v1), unit testing non-Minecraft logic with JUnit 5, MockBukkit for Paper/Bukkit plugin testing (mock server, mock player, event dispatching, inventory checking), integration testing with a test server via Gradle, and GitHub Actions CI workflows that run GameTests headlessly. Includes patterns for mocking registries, testing event handlers, testing commands, and test-driven development for Minecraft projects. Use when the user asks about testing Minecraft mods or plugins, writing GameTests, setting up MockBukkit, or configuring CI for Minecraft projects.
4minecraft-multiloader
Build Minecraft mods targeting both NeoForge and Fabric simultaneously using the Architectury framework for Minecraft 1.21.x. Covers Architectury project structure (common/neoforge/fabric subprojects), ExpectPlatform annotation for platform-specific implementations, shared registry via Architectury's registration API, platform-specific entrypoints, architectury-loom Gradle plugin configuration, gradle.properties for both loaders, multi-jar publishing to Modrinth and CurseForge, and avoiding common pitfalls when sharing code. Use this skill when building a mod that must run on both NeoForge and Fabric with a single shared codebase.
4minecraft-datapack
Create, edit, and debug Minecraft vanilla datapacks for 1.21.x. Covers the full datapack format: pack.mcmeta, function files (.mcfunction), advancements, predicates, loot tables, item modifiers, recipe overrides, tags, damage types, dimension types, worldgen overrides, and structure sets. Handles function syntax, execute command chains, macro functions (1.20.2+), storage NBT, scoreboard operations, advancement triggers, pack format numbers, and /reload workflow. No Java or mod loader required — pure vanilla JSON and .mcfunction files. Use when creating or editing Minecraft datapacks, writing .mcfunction files, configuring loot tables or advancements, or any vanilla datapack development that does not need mod loaders.
4minecraft-server-admin
Set up, configure, and operate Minecraft Java Edition servers for 1.21.x across Paper, Purpur, Folia, Velocity networks, and modded (Fabric/NeoForge) deployments. Covers deployment selection, performance tuning playbooks, plugin operations, proxy/forwarding setup, backup and recovery runbooks, live incident troubleshooting, Docker/Pterodactyl patterns, and security hardening. Use for server infrastructure and operations, not plugin or mod feature development.
3minecraft-ci-release
Set up CI/CD pipelines, automated publishing, and release workflows for Minecraft mods and plugins for 1.21.x. Covers GitHub Actions matrix builds for NeoForge and Fabric, automated publishing to Modrinth (via minotaur Gradle plugin) and CurseForge (via curseforgegradle), GitHub Releases with JAR artifacts, semantic versioning conventions for Minecraft mods, CHANGELOG generation, Dependabot for Gradle wrapper and plugin updates, build caching with gradle/actions/setup-gradle, pull request checks, and release tag workflows. Also covers Paper plugin CI with shadow JAR builds. Use when the task is CI/CD pipelines, release automation, artifact publishing, versioning, or release governance for Minecraft mods or plugins.
3minecraft-commands-scripting
Write Minecraft vanilla commands, NBT scripts, scoreboards, and complex execute chains for use in command blocks, chat, or .mcfunction files. Covers full execute subcommand reference (as/at/in/positioned/rotated/facing/anchored/if/unless/store/run), selector arguments with all filter options, scoreboard objectives and operations, NBT path syntax for entities/blocks/storage, schedule and forceload commands, tellraw/title JSON text components, bossbar, team management, item modification commands, attribute commands, particle/playsound effects, and RCON scripting. Targets Minecraft 1.21.x Java Edition. Use for command-only work; for full function/advancement/recipe systems use the minecraft-datapack skill instead.
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