| name | minecraft-essentials |
| description | Install, upgrade, run, migrate, back up, and troubleshoot Minecraft Java servers. Use when Codex needs to work on a Minecraft-only setup such as Vanilla, Paper, Fabric, plugin compatibility, Java versioning, LAN join info, backups, Bedrock bridging, or moving a local server toward a more stable always-on setup. |
Minecraft Essentials
Use this skill for Minecraft Java server work only. This skill is not for general game launchers or unrelated hosting tasks.
Quick Start
- Identify the server type first:
vanilla, paper, fabric, or an existing mixed setup.
- Confirm the current world version, Java version, and whether the server is local-only or meant for outside players.
- Back up the world and key config files before changing jars, plugin stacks, or major versions.
- Prefer Paper for practical multiplayer servers unless the user explicitly needs pure Vanilla or a Fabric mod stack.
- When the user wants broad Java client compatibility, treat ViaVersion, ViaBackwards, and ViaRewind as a compatibility layer on top of a modern Java server, not as a true old-version server.
Workflow
Audit First
- Inspect the server directory before changing anything.
- Confirm:
- current jar or launcher
server.properties
- world folders
- plugin or mod folders
- Java version in use
- how the server is started today
- If the server already boots, preserve the current run path unless there is a clear reason to replace it.
Choose The Right Stack
- Use Paper for:
- stable local servers
- plugin support
- performance and admin tooling
- compatibility plugins like ViaVersion
- Use Vanilla for:
- minimal pure-Minecraft setups
- users who do not want plugins
- Use Fabric for:
- modded setups that depend on Fabric mods
- cases where plugin ecosystems are not enough
- Do not mix Paper plugins and Fabric mods unless the user explicitly wants a hybrid approach and understands the tradeoffs.
Versions And Compatibility
- Match the underlying world and server version carefully before upgrading.
- Explain clearly when a compatibility plugin lets older clients join a newer server.
- If the user wants Bedrock support, that is a separate bridge layer such as Geyser, not a Java-version compatibility plugin.
- Before major upgrades:
- back up the world
- back up launch scripts
- call out any likely world format migration
Required Deliverables
- A clear summary of the current Minecraft setup.
- The chosen server path and why it fits.
- Updated run scripts or launch instructions when needed.
- Join info for:
- same machine
- same LAN
- hostname if available
- A backup path before risky changes.
Plugin And Mod Guidance
- Keep plugin stacks focused. Add only what solves the actual player/admin need.
- Common Paper lanes:
- compatibility: ViaVersion, ViaBackwards, ViaRewind
- Bedrock bridge: Geyser, Floodgate
- admin: permissions, moderation, backups
- quality of life: homes, claims, anti-grief
- Verify plugin version compatibility with the target server version before adding them.
Networking And Safety
- For LAN-only setups, surface
localhost, the machine LAN IP, and the hostname.
- For internet exposure, explain the difference between local hosting, port forwarding, and VPS hosting.
- Call out that opening a Minecraft server to the public increases security and moderation needs.
- If the user wants 24/7 uptime, prefer moving toward a VPS or managed host instead of pretending a sleeping laptop is reliable infrastructure.
Editing Guidance
- Keep launch scripts readable and easy to rerun.
- Prefer one obvious launcher per server mode.
- Do not delete world data, dimension folders, or plugin data unless the user explicitly asks.
- Explain migrations plainly, especially world layout changes and compatibility-layer limits.
Resources
scripts/mc_lan_info.sh: prints same-machine, LAN, and hostname join targets for a local Minecraft server.
references/server-modes.md: when to choose Vanilla, Paper, or Fabric.
references/plugin-packs.md: practical plugin bundles for compatibility, Bedrock, admin, and QoL.
references/operations-checklist.md: backup, upgrade, migration, and exposure checklist.