ISC-RAG studies whether ingest-time extraction of atomic, source-linked facts improves retrieval-augmented generation over conventional text chunking for real human dialogue.
- RAG Deserves an Index: Why Ingest-Time Compilation Beats Query-Time Interpretation (repository PDF, arXiv PDF, DOI) — the position paper reporting this repository's document-disjoint retrieval and QA comparison alongside the ISC maintenance result.
- Cost Scales with Change, Not Corpus Size: Incrementally Maintaining an Evolving Semantic Substrate (PDF, DOI) — the companion incremental-maintenance study.
Venue status: RAG Deserves an Index is CIDR 2027 submission #150. It is public on arXiv but has not yet been accepted; CIDR author notification is due October 6, 2026.
The complete chronological record is in CHANGELOG.md. The reconstructed study token estimate separates directly metered usage from estimated components.
The frozen held-out study used 500 document-disjoint MediaSum transcripts and 499 source-grounded questions. At the 2,048-token answer budget, compiled facts reached 85.2% answer accuracy with roughly 2,200 prompt tokens per question, compared with 72.5% using roughly 16,300 tokens for the strongest ordinary chunk configuration. An Anthropic-style contextual-retrieval stack reached comparable accuracy, but used about 21 times as many query-path tokens and did not provide exact-quote-validated provenance.
These are controlled results over one dialogue corpus. The detailed conditions, corrections, failed attempts, and statistical tests are documented in:
- held-out protocol
- held-out results
- contextual-retrieval baseline
- paired McNemar tables
- raw-result audit
The canonical store is PostgreSQL with pgvector. All retrieval conditions use the same Nomic embedding model and answer/evaluation machinery while varying the retrieval representation:
| Representation | Retrieval payload |
|---|---|
| Fixed chunks | Overlapping transcript windows |
| Turn-aware chunks | Consecutive dialogue turns grouped to a size target |
| Semantic chunks | Consecutive turns grouped by lexical cohesion |
| Compiled facts | Self-contained fact text plus exact supporting quotation and source coordinates |
| Contextual retrieval | Fixed chunks prepended with generated document context, optionally combined with BM25 and reranking |
The fact-pipeline design defines extraction, validation, provenance, and serving contracts. The storage design defines canonical records, embeddings, and index synchronization.
cmd/ Go command-line entry points
internal/ ingestion, extraction, embedding, retrieval, and evaluation
internal/storage/ PostgreSQL and pgvector migrations
experiments/ frozen run ledgers, aggregate statistics, protocols, and tools
examples/ deterministic sample membership and question fixtures
docs/ design records, experiment reports, and limitations
resources/mediasum/ acquisition manifest and provenance; no corpus files
results/ public, source-text-free result SQL
sources/MediaSum/ pinned official MediaSum repository submodule
Requirements: Go, Docker, and a Fireworks API key.
git clone --recurse-submodules https://github.com/dorkitude/ISC-RAG.git
cd ISC-RAG
cp .env_example .env
# Add FIREWORKS_API_KEY to .env.
docker compose up -d postgres
./bootstrap.sh --accept-mediasum-research-use
go run ./cmd/isc-rag migrateThe bootstrap command requires explicit acknowledgement of the MediaSum
research-use notice, verifies Go, loads the ignored local .env, and verifies
or downloads the pinned files atomically with SHA-256 validation.
The code and original project documentation are released under the MIT License. MediaSum's authors request research-only use and citation. The upstream repository does not provide an explicit license, so the 4.45 GB corpus is not relicensed or copied into this repository. Instead, the pinned downloader obtains it from the upstream mirror and verifies every file. See MEDIASUM-NOTICE.md before downloading or using it.
Source-derived research fixtures and calibration materials are retained so the study can be inspected and rerun. They remain subject to the MediaSum research-use request and the rights in the underlying NPR/CNN transcripts; the repository's MIT license does not override those terms. Full database backups are not distributed because they contain hundreds of complete transcripts.
The public SQL contains experiment configuration, counts, token totals, and aggregate verdicts only. It intentionally excludes documents, turns, facts, quotes, questions, reference answers, generated answers, citations, and model prompts/completions. See results/README.md.
The frozen public ledgers identify the runs behind the reported comparisons.
Reproducing source-bearing rows requires independently obtaining MediaSum under
its research-use terms through
./bootstrap.sh --accept-mediasum-research-use and rerunning the pipeline.
Provider model availability
and pricing can change; model identifiers and the dates used by the study remain
recorded in the experiment documentation.
The authoritative project roadmap is PLAN.md.