Rule books

A rule book is a JSON file declaring explicit load-order relationships between creations. Rule books outrank LOOT and Categories — they exist to correct those sorters when they get something wrong.

File format (sketch)

{
    "name": "My ship overhaul patches",
    "description": "Load patch after its donor ships",
    "enabled": true,
    "rules": [
        { "type": "load_after",  "plugin": "MyPatch.esp",     "relative_to": "ShipPackA.esm" },
        { "type": "load_before", "plugin": "SomeTweak.esp",   "relative_to": "MyPatch.esp"   }
    ]
}

Rule types mirror the core constraint vocabulary. References are plugin filenames as they appear in Plugins.txt. A rule that references a plugin you don't have installed is silently inert — not an error.

Curated vs user

The toolkit ships a set of curated rule books in a read-only directory alongside the binary. These are project-authored (some generated by the Description parser, some hand-written) and distributed with the release.

User rule books live in a separate, writable directory under the tool's data folder — see File locations. You create these through the editor or by dropping JSON files in by hand.

Precedence

Against other sorters, rule books sit above LOOT (20) and Categories (10) but below TES4 (100). Curated rule books emit at priority 30; user rule books emit at priority 40 and above, with later-loaded user books getting higher numbers. The practical ordering:

1. TES4 masters always win.
2. User rule books outrank curated rule books.
3. Among user rule books, later-loaded files outrank earlier ones.
4. Rule books (curated or user) outrank LOOT and Categories.

This means if you don't like what a curated rule book does, you can override it with a one-line user rule book — and if LOOT or Categories is putting a creation in the wrong spot, a single rule book entry fixes it without waiting for those sources to update.

Source attribution

Every emitted constraint carries the source rule book's filename, which is what lets the Hint dialog show you exactly which file caused a move. For example: RULE:001_patch_description_parsing_high.json.

Round-tripping through the editor

The editor presents a drag-reorder list rather than a raw rules list. Saving converts the ordering into a chain of load_after rules between consecutive items. Loading a rule book back into the editor reverses that — but only if the rules form a consistent chain. Hand-authored rule books with more complex topology still load for sorting purposes; the editor just refuses to open them.