NEWS.md
In ragnar: Retrieval-Augmented Generation (RAG) Workflows

ragnar 0.2.0

ragnar_store_create() gains a new argument: version, with default 2. Store version 2 adds support for chunk deoverlapping on retrieval and automatic chunk augmentation with headings. To support these features, the internal schema and ingestion requirements are different. See markdown_chunk() and new S7 classes MarkdownDocument and MarkdownDocumentChunks. Backwards compatibility is maintained with version = 1. (#58, #39, #36)
ragnar_store_create() now supports Date and POSIXct classes supplied to extra_cols.
ragnar_store_create() now supports remote MotherDuck Databases specified with md:<dbname> as the location argument. (#50)
ragnar_retrieve() and friends gain a filter argument, adding support for efficiently filtering retrieval results.
ragnar_retrieve_bm25() gains arguments b, k, and conjunctive (#56).
ragnar_retrieve_vss() gains argument query_vector, supporting workflows that preprocess the query string before embedding.
ragnar_retrieve_vss() set of valid method choices have been updated to a narrower set to ensure that an HNSW index scan is used.
Passing a tbl(store) to ragnar_retrieve() is deprecated.
New chunker markdown_chunk() with support for chunk heading context generation, semantic boundary selection, overlapping chunks, document segmentation, and more. (#56)
New function embed_google_vertex() (@dfalbel, #49)
New function embed_databricks() (@atheriel, #45)
New function ragnar_chunks_view() for quickly previewing chunks (#42)
ragnar_register_tool_retrieve() gains optional name and title arguments to allow for more descriptive tool registration. These values can also be set in ragnar_store_create() (#43).
ragnar_read() and read_as_markdown() now accept paths that begin with ~ (@topepo, #46, #48).
Changes to read_as_markdown() HTML conversion (#40, #51):
New arguments html_extract_selectors and html_zap_selectors provide a flexible way to exclude some html page elements from being included in the converted markdown.
code blocks now include the language, if available.
Fixed handling of nested code fences in markdown output.