Editing Architecture (section)

== Core composition pattern ==

Three levels:

# '''Core protocol''' (duralex): defines WHAT can be done (DocumentStore protocol, SearchEngine protocol).
# '''Country implementation''' (duralex-fr): implements HOW for a specific jurisdiction (formatters, reference resolvers, tag schemas).
# '''Application''' (duralex-mcp): composes protocols + implementations at startup.

'''Reference resolution''' uses <code>TagQuery</code> as the universal interface between jurisdiction parsers and the store. This is a core architectural decision — all reference resolution across all jurisdictions flows through TagQuery. There are no typed reference classes per jurisdiction.

* Core defines: <code>TagQuery</code> dataclass (<code>language</code>, <code>kind</code>, <code>tag_filters: TagFilterSet</code>, <code>should_sort_in_force_first</code>, <code>at_date</code>) and <code>TagFilterSet</code> (immutable tuple of <code>TagFilter</code> predicates with operators EQ/IN/NOT_IN/ILIKE/EXISTS/NOT_EXISTS/NORMALIZE). See [[MCP/Reference resolution]].
* Jurisdiction plugin (e.g., duralex-fr): parses "article 1240 du code civil" into <code>TagQuery(language="fr", kind="legislation", tag_filters=TagFilterSet.from_tags({"article_number": "1240", "code": "Code civil"}))</code>.
* Store: translates <code>TagQuery</code> to SQL via the shared <code>build_tag_filter_conditions</code> builder (generic, zero jurisdiction knowledge).