The canonical protocol documents live in docs/protocol/.
- Protocol index and document classifications
- VGI Filter Encoding v2 — normative proposed specification
- Runtime-filter artifacts — proposed optional extension
- DuckDB filter adapter — informative implementation guide
- Catalog query pushdown — proposed implementation design
- DuckDB 2.0 protocol design/audit report — informative
The executable language-neutral conformance corpus and retargetable worker runner are in
conformance/filter-v2/.