# Glossary

| Term | Definition |
|------|------------|
| **ADR** | Architecture Decision Record -- a document capturing an architectural decision |
| **BM25** | Best Matching 25 -- a ranking function used by FTS5 for keyword search |
| **FTS5** | Full-Text Search 5 -- SQLite extension for full-text indexing |
| **JSONL** | JSON Lines -- one JSON object per line, newline-delimited |
| **Model2Vec** | A library for static (uncontextualized) word embeddings |
| **RRF** | Reciprocal Rank Fusion -- method for merging ranked lists from multiple retrievers |
| **ULID** | Universally Unique Lexicographically Sortable Identifier |
| **WAL** | Write-Ahead Logging -- SQLite journaling mode enabling concurrent reads |
| **potion-base-8M** | The specific Model2Vec model used (~8 MB, 256 dimensions) |
| **Scope** | The architectural domain a guardrail applies to (from taxonomy) |
| **Taxonomy** | The configurable vocabulary of allowed scope values |
