DevTools, the World Inspector

DevTools is a client-side Fabric mod for versions through 26.x-1.19.x that adds a powerful Inspect mode to your game. By freezing your movement and unlocking your cursor, you can point at blocks, fluids, dropped items, and entities to read rich, debug-style data directly on your screen.

It features customizable layouts, deep NBT-style data dumps, and clipboard copying.

Requirements & Versioning

Requirement Version / Constraint Notes Minecraft 26.x-1.19.x Compatible with 26.x/1.21.x/1.20.x/1.19.x releases. Mod Loader Fabric >=0.18.6 Client-side only. Safe to leave in your mods folder when joining servers. Fabric API * (Any version, but the latest is reccomended) Required for core mod functions.

Quick Start

1. Install Fabric, then drop DevTools and the Fabric API mod into your mods folder.
2. Launch the game and enter a world.
3. Press F6 (default) to toggle Inspect mode.
4. Move your mouse over blocks or creatures, and Left-Click to select them.
5. Press M to expand detailed data for your selected target.
6. Head to Options → DevTools… to tweak colours, toggle data lines, or change the layout.

How Inspect Mode Works

When you turn Inspect mode on, the game adjusts your interactions so you can focus on the environment data.

Feature Behaviour Movement You stay completely still. Movement is suppressed so you do not accidentally walk away from your inspection point. Mouse Freedom Your cursor is unlocked. Vanilla left-click does not punch blocks or attack; it is used exclusively for selecting targets. Smart Raycasting The mod picks targets based on camera + cursor. You can target blocks, flowing fluids, item entities on the ground, XP orbs, and mobs. World Outlines A thin outline shows what you are hovering over. A thicker, brighter outline shows what you have selected. Scrolling Use your mouse wheel over the info panel to scroll through long text.

Keybinds

All keys can be remapped under Controls → DevTools. The info panel always displays the actual names of the keys you have currently bound.

Action Default Key Description Toggle Inspect F6 Turns Inspect mode on and off. Select Target Left Mouse Locks the HUD onto the hovered block/entity. More Info M Toggles the detailed NBT/data dump. Free Player Hold L-Alt Restores movement and camera while keeping Inspect on. Copy Value Hold L-Ctrl Click any line in the HUD to copy its value to your clipboard.

Free Camera (Alt Mode)

If you hold Left Alt, you temporarily get your movement and camera controls back. Raycast updates are frozen, so the outlines stay fixed to your last targets, and the HUD becomes transparent so you can see the world.

Menu Suspensions

Opening any fullscreen menu (for example the Pause or Inventory screen) suspends and freezes raycasting and its updates, so you won't mess up your selection.

The Info Panel (HUD)

The HUD is designed to provide immediate summary data, with the option to expand into detailed categories.

• Header: Shows if you are HOVERING or have a target SELECTED. Includes the icon of the selected block/entity, display name, and registry ID. Rarity colours automatically match vanilla Minecraft tiers (common, uncommon, rare, epic).
• Summary: Quick facts like coordinates, HP for living entities, or drop info for items.
• Detailed Info ("More Info"): Hitting M opens a categorized text dump. Default category order: Source, Item Form, State Properties, Block Data, BlockEntity, Environment, Type, Identity, State, Living, Equipment, Effects, Mob, Raw NBT.
• Boolean Styling: true / false lines are coloured distinctly for quick scanning.
• Copy Feedback: Successfully copying a line flashes a quick "copied" message.

Settings Menu

Options → DevTools… opens the settings menu. The button is placed under the FOV slider, in the middle.

Button Opens HUD Submenu for Colours and Preferences Keybinds Vanilla Key Bindings screen Layout Panel corner positioning and category ordering

Configuration File (devtools.properties)

Location: .minecraft/config/devtools.properties

Key Type Purpose tutorialSeen true / false Tutorial already shown / skipped forever hud.color.<name> 8 hex digits AARRGGBB HUD colour overrides (see table below) pref.<key> true / false Per-line / per-section HUD preference layout.position TOP_LEFT, TOP_RIGHT, BOTTOM_LEFT, BOTTOM_RIGHT Inspector panel corner layout.categoryOrder Comma-separated names Custom More info category order

HUD Colours Screen

Each line has a colour square, a hex code field, a copy button, and a reset button. Clicking the square opens a colour picker with Hue, Saturation, and Brightness sliders.

HUD Colour Keys (hud.color.*)

Config suffix UI label Role bg Background Panel fill borderTop Border (top) Top accent line headerBg Header background Header band header Header label “HOVERING” / “SELECTED” text category Category label Section titles in dumps key Property key Text before : value Property value Text after : dim Dim text Hints / secondary lines scrollbar Scrollbar track Scroll gutter scrollThumb Scrollbar thumb Scroll handle boolTrue True value Boolean badge / styling boolFalse False value Boolean badge / styling

(Note: Item rarity colours are strictly tied to vanilla and are not configurable here).

HUD Preferences Screen

You can toggle exactly which lines show up. The top row, All Preferences, sets every other box on or off together.

General Preferences

Key Label pref.showIcon Show icon pref.showId Show identifier

Block-related Preferences

Key Label pref.block.source Source mod pref.block.destroyTime destroyTime pref.block.resistance resistance pref.block.lightEmit lightEmit pref.block.lightDamp lightDamp pref.block.friction friction pref.block.speedFactor speedFactor pref.block.jumpFactor jumpFactor pref.block.isSolid isSolid pref.block.isAir isAir pref.block.liquid liquid pref.block.blocksMotion blocksMotion pref.block.canOcclude canOcclude pref.block.redstone redstone pref.block.randomTick randomTick pref.block.ignitedByLava ignitedByLava pref.block.stateProps State properties pref.block.blockEntity Block entity NBT pref.block.environment Environment (biome/light)

Entity-related Preferences

Key Label pref.entity.source Source mod pref.entity.category category pref.entity.dimensions dimensions pref.entity.fireImmune fireImmune pref.entity.uuid UUID pref.entity.customName customName pref.entity.tags tags pref.entity.onGround onGround pref.entity.invulnerable invulnerable pref.entity.silent silent pref.entity.glowing glowing pref.entity.noGravity noGravity pref.entity.frozen frozen pref.entity.inWater inWater pref.entity.onFire onFire pref.entity.HP HP pref.entity.armor armor pref.entity.isBaby isBaby pref.entity.effects Active effects pref.entity.equipment Equipment pref.entity.noAI noAI pref.entity.persistent persistent pref.entity.leftHanded leftHanded pref.entity.target target pref.entity.owner owner pref.entity.rawNbt Raw NBT

Layout Screen

Control Cycles through Window position Top Left → Top Right → Bottom Left → Bottom Right Ordering Default, then “<Category> First” for each known category.

Remember to press Save on the Colours, Preferences, and Layout screens to keep your changes.

Project Metadata & Links

Mod ID devtools Authors Beef and Capybarabeef Studios under Miljö AB Source Code GitHub Repository Issue Tracker GitHub Issues

License

DevTools is released under the MIT License. The complete legal text is available in the LICENSE file at the repository root.