Users Worldgen Info Troubleshooting

Troubleshooting

Nothing shows up in the viewer

1. Check that the mod is installed on both the client and the server.
2. The client asks the server for the data while the recipe viewer loads, at game/world start — not when a category is opened. On a large pack that transfer takes a moment.
3. Check the server log at startup for Started reading worldgen info — the scan happens there, and failures are logged there.
4. Worldgen data is per world. Outside a loaded world there is nothing to show.

The game will not start, or tooltips show keys like aci.util.tag

Advanced Core Info (ACI) is missing or is the wrong version for your Minecraft version and loader. It is a required library — see Getting Started. A refusal to launch names aci in the loader's error screen; a partially loaded setup shows untranslated aci.util.* keys in the tree instead of readable text.

A dimension is missing

A dimension whose biomes produced nothing at all is dropped, and the log says so (Level <id> was dropped - it contains no non-empty biome nodes). Dimensions with a generator that is not noise-based have no base terrain to report; if their biomes also place no features, there is nothing left to show.

A dimension can also be hidden on purpose by the dimensions option — in your own config file or, on a dedicated server, in the server's. See Configuration.

A biome's base terrain looks incomplete

The base blocks are found by running the biome's surface rule over synthetic columns, not by reading a list — see Overview. A block a rule only places in a very rare situation can be missed, and the result legitimately differs between seeds. The generator's default block and fluid are always listed even though no rule places them.

A feature lists a block it never places

Part of a feature's blocks is recovered by analysing its placement code, which is a static approximation:

• Blocks that depend on which configuration the feature was given are hidden by default; if you turned showConfigConditionalBlocks on, that is what you are seeing. See Configuration.
• A guard the analysis cannot recognise leaves the block listed unconditionally — warped fungus lists weeping vines, which only crimson fungus grows.

A feature is missing a block it does place

• The block comes from an NBT structure (fossils and anything else built from a template) — no static analysis reaches those.
• The block is placed through an indirect game mechanic: a sculk patch reports the sculk blocks and sensors it grows, but not sculk veins.
• minecraft:air, minecraft:cave_air, minecraft:void_air and minecraft:barrier are never displayed.

A tooltip shows unformatted data under "Auto-detected", or says "Not implemented"

AWI does not recognise that placement modifier / provider / predicate, so it shows its raw data instead of dropping it. Up to 26.2 a feature configuration it does not know is labelled Not implemented rather than auto-detected; its blocks are shown either way. Nothing is broken — a readable description has to come from the mod that added it (developer docs).

Server startup is slow / a lot of memory is used

The whole worldgen tree is built once at server start, on the server thread, and kept in memory. The base-terrain scan is the expensive part — roughly two thirds of the total. It scales with the number of dimensions and biomes, so a pack that adds hundreds of biomes pays for all of them. Turn logMoreStatistics on to see where the time goes, per dimension and per biome, and turn it back off afterwards. Dimensions hidden with dimensions are not scanned at all.

I changed the config and nothing happened

The config file is read while the mod starts. Restart the game or the server. The worldgen data is built once when the world loads and /reload does not rebuild it — load the world again after changing worldgen datapacks. Block tags shown in the tree do follow /reload.

My config file was reset

That happens when the config format version changes with a mod update. The old file is kept next to it as a timestamped backup such as awi_common.json.2026-10-06_14-30-05.bak; re-apply your changes onto the newly generated file. See Configuration.

Reporting a bug

Include the Minecraft version, loader, recipe viewer, AWI version, the log, and — if it concerns a specific block — which dimension, biome and feature it is about: https://github.com/yanny7/AdvancedLootInfo/issues

For questions that are not bug reports, there is also a Discord.