Just Enough Resources Mod FAQ
18 questions players actually ask, answered.
How do I get JER to show up in JEI?
JER works automatically once both it and JEI are installed, adding extra tabs and tooltips to JEI's existing item and mob views. If nothing appears, make sure JEI is loaded and check that you're looking at a mob or ore item rather than a crafting recipe.
How do I see what a mob drops?
Open JEI, search for the mob's spawn egg or its entity entry, and hover over it to see the drop list JER adds. The drops are shown with their chance percentages, so you can tell rare drops from guaranteed ones.
How do I check where a specific ore spawns?
Search the ore block or its drop in JEI and hover over it; JER adds a world-gen tab showing which dimensions and Y-levels it appears at. You can also open the ore's dedicated JER page to see the distribution graph.
What does the ore distribution graph actually show?
The graph plots ore frequency against Y-level for each dimension the ore generates in, so you can see the height band where it's most common. Peaks mean more ore at that level, and flat or empty regions mean none spawns there.
How do I look up dungeon or chest loot?
Find the loot table entry in JEI (often listed under chests, dungeon loot, or structure loot) and hover it to see the possible items and their weights. JER shows the pool contents rather than a single guaranteed drop.
How do I use the /profile command?
Run /profile with a chunk amount and optionally 'all' to scan a generated world and produce a world-gen-scan.json in your JER config folder. This captures the actual ore distributions from that world so you don't have to guess them.
How do I make my own ore distribution with DIY mode?
Add a world-gen.json to the JER config folder describing your ore distributions, then toggle the DIY setting in-game to make JER use your file instead of the defaults. This is aimed at pack makers and experienced players.
Why isn't my custom world-gen.json doing anything?
The most common cause is forgetting to enable the DIY setting in-game, or placing the file in the wrong folder. Double-check the file is valid JSON and named exactly world-gen.json in the JER config directory.
Does JER work with modded ores and mobs?
Yes, JER reads data from other mods and will show drops and ore generation for modded content as long as those mods expose the relevant data. Some mods may not provide full world-gen info, in which case JER shows what it can.
Does JER hurt performance?
JER is mostly a display and data-reading mod, so its normal impact is minimal. The heavier operations are the /profile world scans and DIY graph generation, which are one-off tasks rather than continuous background work.
How do I open the JER resource screens in JEI?
Open your inventory or JEI's item list, hover over the item, block, or mob you want to inspect, and press the JEI recipe/uses key (default R or U). JER adds extra tabs and pages to that JEI screen showing mob drops, dungeon loot, ore generation, or plant drops depending on what you're viewing.
Why don't I see any ore generation graphs in JEI?
Ore gen data only appears for blocks that actually generate in the world and are registered with world-gen info. If a mod's ore has no data, or you're looking at a block that doesn't spawn naturally, JER has nothing to graph. Make sure JEI is installed and JER is loaded alongside it.
How do I check dungeon loot tables?
Hover over a chest or the relevant loot item in JEI and open the uses view; JER shows the dungeon loot table entries and their relative weights. This works for structures JER has loot data for, like dungeons, mineshafts, and similar generated containers.
Where does world-gen-scan.json go?
It's written to the JER config folder, the same place world-gen.json lives. You can rename or copy it to world-gen.json to feed your scanned distributions back into JER.
How do I make my own ore distribution with the DIY setting?
Add a world-gen.json file to the JER config folder, then toggle the DIY setting in-game (via the JER config screen or the relevant keybind/command). Once DIY is on, JER reads your file instead of the built-in data, so your custom ore graphs appear in JEI.
What's the difference between world-gen.json and world-gen-scan.json?
World-gen.json is the file JER reads to display ore distributions, and you edit it to define custom ones. world-gen-scan.json is output written by /profile from a real generated world, which you can adapt into world-gen.json.
Does JER work without JEI?
No. JER is a JEI integration mod, so JEI must be installed for its screens and tabs to appear. Without JEI, JER has nothing to attach its resource views to.
Does JER cause lag or performance issues?
JER itself is lightweight during normal play since it mostly reads data and renders JEI pages. The main cost is running /profile, which scans chunks and can take a moment on large chunk amounts, so use it sparingly on big worlds.