Data-Driven Registration

Trap: the old layout does not match the current implementation. The layout described by earlier upstream docs is data/<modid>/kasugalib/*.json (flat files, a sources field), which is deprecated. The current contract is the index directory data/<modid>/kasuga_lib/data_driven/ plus the content directory data/<modid>/kasuga_lib_content/.

Reference pages (this directory):

Document	Type	Content
schema.md	Reference	Fields, types, D1–D6 rules, and error classification for the index manifest and content files
api-registration.md	Reference	Registration-phase entry point JsonTreeBuilder, the index API, content dispatch, and conflict resolution
api-extension.md	Reference	The TypeHandler system, BuildContext, FactoryRegistry, and property parsers
api-diagnostics.md	Reference	The Diagnostics facade, the /kasuga_data command, and error classification
api-reload.md	Reference	The reload API, the assertable pure-function surface, and call examples

Section-number cross-reference: the four api-*.md pages in this directory were once the same page, api.md; after being split by reader task they kept their original section numbers, so that the §N cross-references already written throughout the tree stay valid — which is why the numbering inside each page is not contiguous:

Page	Original section numbers
api-registration.md	§1 module and package structure, §2 JsonTreeBuilder, §3 index API, §4 content dispatch and apply, §5 conflict resolution
api-extension.md	§8 TypeHandler system, §9 BuildContext / RegBuildContext, §10 FactoryRegistry, §11 property parser
api-diagnostics.md	§6 Diagnostics facade, §7 /kasuga_data errors command, §12 error classification
api-reload.md	§13 reload API, §14 pure-function surface assertable from tests, §15 call examples

Getting started and tutorials (the guides/ section):

Document	Type	Content
intro.md	Tutorial	The getting-started path from an empty directory to a block that moves
guide-content.md	How-to	Content organization, group inheritance, last-wins, verification, and troubleshooting
guide-extension.md	How-to	Custom TypeHandler / factory / property compiler / ReloadHandler

For an overview of the mechanics, see Data-driven registration fundamentals.

The few still-valid limitations from the old upstream pages (models/textures and translation keys are not generated automatically, the coverage of the built-in item property parser, and the fact that an embedded BE's data_type cannot be configured from JSON) have been folded into guide-content.md section 7 and guide-extension.md section 10.