Troubleshooting Datapack and Tag Loading Issues

Identifying Data and Tag Errors

Mods that rely on DataPack Anvil use its internal data managers, custom tags, and serializable block predicates to handle advanced gameplay checks. If a datapack-driven mod is not behaving correctly—such as failing to recognize custom tag groupings or ignoring block checks—the issue is often caused by an incomplete reload or a missing library.

Steps to Fix Common Loading Problems

• Check your startup logs: If the game fails to boot, inspect your crash report or log file. If the log complains about missing data types or failed datapack events, ensure DataPack Anvil is active in your mods folder.
• Force a data reload: In an active world, run the /reload command. This prompts DataPack Anvil to re-register its data types and rebroadcast them to your client.
• Check datapack conflicts: If custom tags or predicates are not working, temporarily disable other third-party datapacks in your world's datapacks folder to see if an invalid file is interfering with the data managers.