WorldEdit
sfan5

In-game world editor. Use it to repair griefing or create awesome buildings in seconds.

Edit
Johannes Fritz

Allows copying, pasting, filling, deleting, replacing and saving 3D areas

Meshport (Luanti Mesh Exporter)
random_geek

Easily export areas in Luanti to meshes for 3D rendering.

Protector Redo
TenPlus1

Lets players craft special blocks to protect their builds or disable PVP in areas.

Modgen
BuckarooBanzai

mapgen mod creator

Discord-Minetest Relay
archfan7411

Mod + external program providing Discord relaying and commands.

Areas
ShadowNinja

Areas is a advanced area protection mod based on node_ownership.

Terraform
x2048

Adds terraforming tools to your creative toolbox

Cleaner
AntumDeluge

Remove/Replace unknown entities, nodes, & items.

Bulldozer
celeron55

Driveable bulldozer for pushing nodes and flattening ground

Streetbuilder
seckl

Build a street from given points

Extruder Tool
fgaz

Adds an extruder tool that can extend continuous surfaces towards the node face that was clicked

Public teleport location bookmarks
Hybrid Dog

Add commands to manage public positions of interest

WorldEdit Additions
Starbeamrainbowlabs

Extra tools and commands to extend WorldEdit. Currently has over 70 commands!

Permatime
ROllerozxa

Set the day of time cycle to a certain time permanently.

WorldEdit Maze Generator
wsor4035

A maze generator

Really Flat
rdococ

Generates superflat terrain in whatever material you choose.

SzUtilPack
Warr1024

A collection of misc dependency-free utilities primarily for server hosts

Map Tools
Calinou

Adds various special versions of normal blocks, tools, and other map maintainer tools.

Tools Using the Node Damage and Repair System
Noodlemire

Overrides pre-existing tools to make them cause persistent node damage.

Playtime Recorder
Lejo

Use /playtime to get the time you played

Blockbomber Editor
MisterE

Make arenas for Blockbomber

NextGen Bedrock
StarNinjas

Adds an indestructible bedrock layer at the bottom of the world.

MobConf
zeuner

Place, remove and configure Mobs (for now: NPCs) using chatcommands

Entity Modifier
j8r

Modify the model and size of entities, including players.

World Settings
Codiac

Supports per world settings in Luanti games and mods

Better Command Blocks
ThePython10110

Adds command blocks similar to those from a certain other voxel game.

Remove Unknowns
Clyde

A small tool to help you clean up your world of unknown-blocks.

/giveme itemname completion
Hybrid Dog

Autocompletion of item names for the /giveme chat command

Better Commands
ThePython10110

Adds commands and syntax from a certain other voxel game. Not broken anymore (hopefully)

Classroom
rubenwardy

An easy way to manage students in-game, with support for bulk actions and macros.

Lava + Water > Stone
1F616EMO

Cool Lava into technically special stones for easier cleanup

Essentials
SkyBuilder1717

Adds a lot of helpful commands for your server

Mapserver
BuckarooBanzai

mod for the mapserver

User Manager
1F616EMO

GUI to manage players

Internet Relay Chat
kaeza

Connect your server to an IRC channel, and install irc_commands to control the server from IRC

QA-Block
bell07

A mods development / QA helper

Areas' helper tools
rangeTonic

Convenience tools for Areas protection mod

Player Factions Redo
Pixelated

Rewrites the Player Factions mod to be more efficient and easier to use

Moderator Warnings
1F616EMO

Emphasize warnings sent by the moderation team