Prefab Hash Probe

Reduces log spam from repeated Missing prefab hash warnings in Valheim.

What it does

• Keeps the first identical missing-prefab warning in each scene and suppresses repeats.
• Leaves other warnings and errors untouched.
• Provides optional local diagnostic exports for investigating missing prefab hashes.
• Does not repair missing mods, skip object creation, delete objects, or edit world saves.
• Does not upload data or communicate with an external service.

The underlying missing objects still need to be restored or deliberately removed. Performance improvement depends on how much time was spent logging warnings.

Installation

Install with Thunderstore Mod Manager, then restart Valheim. BepInExPack is required; Jotunn is optional.

For manual installation, copy plugins/PrefabHashProbe/PrefabHashProbe.dll into your profile's BepInEx/plugins/PrefabHashProbe/ directory.

Upgrading from the private diagnostic build: remove the old Local-PrefabHashProbe/PrefabHashProbe.dll before installing this package. Both use the same plugin GUID, local.diagnostics.prefabhashprobe, so only one copy should be installed.

Configuration

On first launch, the plugin creates BepInEx/config/local.diagnostics.prefabhashprobe.cfg:

[Logging]
SuppressRepeatedMissingWarnings = true

[Diagnostics]
EnableDiagnostics = false

Detailed diagnostics are disabled by default. Changing EnableDiagnostics requires restarting the game.

With diagnostics enabled, files are written below BepInEx/diagnostics/PrefabHashProbe/. These include prefab registry and loaded-object names, missing-create attempt counts, sample object IDs and coordinates, installed plugin paths and hashes, and environment details. These files remain local; inspect them before sharing them publicly. Full diagnostics may cause brief pauses while collecting snapshots.

The warning cache tracks up to 10,000 distinct messages per scene. Once full, new untracked warnings pass through; already tracked duplicates remain suppressed.

Compatibility and validation

• Developed against Valheim 1.0.15 / Unity 6000.0.75 and BepInExPack 5.4.2350.
• The earlier private build was used on a Windows client, where suppressing repeated warnings substantially improved the reported frame rate.
• Version 0.2.0 compiles against those installed game/loader assemblies and passes nine isolated warning-filter checks. A complete in-game test of this exact release has not yet been performed.
• Linux, dedicated-server execution, and older game versions have not been runtime-tested. Future game or Jotunn changes may affect the optional diagnostic APIs.

中文说明

本插件保留每种 Missing prefab hash 的第一次警告，并抑制同一场景内的重复警告。它不会修复缺失物品、跳过物品加载、删除对象或修改存档。

默认只限流，不生成诊断文件。需要调查 hash 时，将配置中的 EnableDiagnostics 改为 true 并重启。完整诊断包含本地路径、Mod 清单和部分对象坐标，请检查后再分享。

从此前手动安装的诊断版升级时，请先移除 Local-PrefabHashProbe 内的旧 DLL，避免重复安装。

Development disclosure

This plugin was developed with substantial AI assistance using OpenAI Codex. The Thunderstore listing should include the AI Generated category.