RAG Insight Engine

Modular Retrieval-Augmented Generation (RAG) system for asking grounded questions over your own documents. The project includes pluggable loaders, recursive chunking, HuggingFace embeddings, a persistent Chroma vector store, two retrievers (similarity and MMR), a strict citation-aware Groq LLM generator, a CLI, a Streamlit UI, and an evaluation harness for comparing retrieval strategies.

Features

• Pluggable loaders for PDF and plain text with shared cleanup and metadata enrichment
• Recursive chunking with configurable size and overlap
• HuggingFace sentence-transformer embeddings (MiniLM by default; MPNet supported)
• Persistent Chroma vector store; embeddings reused across runs
• Two retrievers out of the box: similarity and MMR (diverse)
• Strict, citation-aware prompt grounded in document content and metadata
• Stable structured output: every answer comes back as {"answer": ..., "sources": [...]}
• Minimal CLI entry point (app.py)
• Streamlit UI with retriever and top_k controls, source rendering, and raw JSON view
• Evaluation harness (evaluate_rag.py) for sweeping chunk sizes, embeddings, and retrievers

Project Structure

RAG-Insight-Engine/
├── data/
│   └── raw/                      # Drop your .pdf and .txt files here
├── chroma_db/                    # Persistent Chroma index (auto-created, gitignored)
├── loaders/
│   ├── common.py                 # clean_text + metadata enrichment
│   ├── pdf_loader.py             # PyPDFLoader-based PDF ingestion
│   └── text_loader.py            # TextLoader-based .txt ingestion
├── splitters/
│   └── chunker.py                # RecursiveCharacterTextSplitter wrapper
├── embeddings/
│   └── embedder.py               # HuggingFaceEmbeddings wrapper
├── vectorstore/
│   └── chroma_store.py           # Chroma create / load / get-or-create
├── retrievers/
│   ├── base_retriever.py         # Unified get_retriever(kind, k)
│   └── mmr_retriever.py          # Thin compatibility wrapper
├── llm/
│   └── generator.py              # Groq ChatGroq + grounded prompt + RAGAnswer
├── pipeline/
│   └── rag_pipeline.py           # End-to-end RAGPipeline orchestrator
├── utils/
│   ├── config.py                 # Single source of truth for all knobs
│   └── logger.py                 # Idempotent stdout logger
├── app.py                        # Minimal CLI
├── streamlit_app.py              # Streamlit UI
├── evaluate_rag.py               # Retrieval / generation evaluation harness
├── pyrightconfig.json
├── requirements.txt
├── .env.example
└── README.md

Tech Stack

• Python 3.11+
• LangChain (langchain, langchain-community, langchain-core, langchain-text-splitters)
• LangChain integrations: langchain-chroma, langchain-huggingface, langchain-groq
• ChromaDB (persistent vector store)
• HuggingFace sentence-transformers (MiniLM, MPNet)
• Groq Chat API (llama-3.3-70b-versatile by default)
• Streamlit (UI)
• pypdf (PDF parsing)

Local Setup

1) Clone and install

git clone https://github.com/M-Wajeeh/RAG-Insight-Engine.git
cd RAG-Insight-Engine

python -m venv .venv
# Windows PowerShell
.\.venv\Scripts\Activate.ps1
# Linux/macOS
# source .venv/bin/activate

pip install -r requirements.txt

2) Configure secrets

copy .env.example .env
# Linux/macOS: cp .env.example .env

Edit .env and set your Groq key:

GROQ_API_KEY=your_groq_api_key_here

Get one from https://console.groq.com/.

3) Add documents

Drop the PDFs and .txt files you want to query into data/raw/.

4) Run the CLI

python app.py

The first run will:

1. Load documents from data/raw/.
2. Chunk and embed them.
3. Persist a Chroma index in chroma_db/.
4. Print the answer plus its sources as JSON.

Subsequent runs reuse the persisted index, so they start fast.

5) Run the Streamlit UI

python -m streamlit run streamlit_app.py

Dashboard: http://localhost:8501

6) Run the evaluation harness

Compare retrievers, chunk sizes, and embeddings against a fixed query set.

# Retrieval-only sweep across chunk sizes (fast, no LLM calls)
python evaluate_rag.py --queries 6 --chunk-sizes 300 500 800 `
    --embeddings minilm --retrievers similarity mmr --top-k 4 --skip-answers

# Full sweep including LLM-generated answers and grounding checks
python evaluate_rag.py --queries 6 --chunk-sizes 500 `
    --embeddings minilm mpnet --retrievers similarity mmr --top-k 4

For each (chunk_size, embedding) configuration the script prints:

• retrieved chunks per retriever
• generated answer (when not --skip-answers)
• cited sources
• grounding signals (fallback used? duplicate sources?)

CLI Output Format

RAGPipeline.ask(query) and generate_answer(...) always return the same shape:

{
    "answer": "...",
    "sources": [
        {"file_name": "NIPS-2017.pdf", "page": 0, "title": "Attention is All you Need"},
        ...
    ],
}

Example CLI run:

=== QUERY ===
Tell about Table 1

=== ANSWER ===
Table 1 reports maximum path lengths, per-layer complexity, and minimum number
of sequential operations for self-attention, recurrent, convolutional, and
restricted self-attention layers [Source 1].

=== SOURCES ===
[
  {"file_name": "NIPS-2017.pdf", "page": 5, "title": "Attention is All you Need"},
  ...
]

The prompt itself enforces strict grounding: if no field in the retrieved context (content, title, authors, abstract, page) supports the answer, the model returns the exact string Not found in the provided documents. instead of hallucinating.

Streamlit Dashboard

The Streamlit UI includes:

• Retriever selector (similarity or mmr)
• top_k slider (1–20)
• Question input
• Answer panel
• Sources panel with file name, page, and title
• Expander with the raw structured RAGAnswer JSON

The pipeline (embeddings + vector store + LLM client) is cached per (retriever_kind, top_k) via st.cache_resource, so the heavy work happens once instead of on every click.

Configuration

All knobs live in utils/config.py:

Setting	Default	Notes
DATA_PATH	data/raw	Document source folder
CHROMA_DB_DIR	chroma_db	Persisted vector store
CHUNK_SIZE	500	Characters per chunk
CHUNK_OVERLAP	50
TOP_K	4	Retrieved chunks per query
MMR_FETCH_K_MULTIPLIER	2	fetch_k = TOP_K * multiplier
DEFAULT_RETRIEVER	similarity
EMBEDDING_MODEL	sentence-transformers/all-MiniLM-L6-v2	Override per call if needed
GROQ_MODEL	llama-3.3-70b-versatile	Any current Groq chat model
TEMPERATURE	0	Lower = more grounded

How It Works

1. Load — loaders/ reads PDFs and .txt files from data/raw/, cleans whitespace, and tags each document with file_name metadata.
2. Chunk — splitters/chunker.py recursively splits documents into ~500-char chunks with 50-char overlap.
3. Embed — embeddings/embedder.py runs each chunk through a HuggingFace sentence-transformer (MiniLM by default).
4. Store — vectorstore/chroma_store.py writes a persistent Chroma index. On subsequent runs it loads the existing index instead of recomputing embeddings.
5. Retrieve — retrievers/base_retriever.py exposes get_retriever(kind, k) for similarity or mmr search.
6. Generate — llm/generator.py formats retrieved chunks and their metadata into a strict prompt, calls Groq, and returns RAGAnswer = {"answer": str, "sources": list[Source]}.
7. Orchestrate — pipeline/rag_pipeline.py wires steps 1–6 into a single RAGPipeline.ask(query) call. app.py and streamlit_app.py are thin front-ends over this pipeline.

Evaluation

evaluate_rag.py is the canonical way to measure changes. It supports:

• Retriever comparison — --retrievers similarity mmr runs both against the same vector store for fair comparison.
• Chunk-size sweep — --chunk-sizes 300 500 800 rebuilds the index per size and re-runs the same queries.
• Embedding comparison — --embeddings minilm mpnet tests how a stronger embedding model affects retrieval.
• Retrieval-only mode — --skip-answers avoids LLM calls when you only care about which chunks come back.
• Grounding signals — for every answered query, the script prints whether the model fell back to the "not found" string and whether the retrieved chunks repeat sources.

The default test query set covers common research-paper questions:

TEST_QUERIES = [
    "What is the main contribution?",
    "What problem does the paper solve?",
    "Explain the methodology",
    "What are the limitations?",
    "Summarize the paper",
    "Tell about Table 1",
]

Troubleshooting

Streamlit shows Not found in the provided documents. for everything

• Make sure your documents actually live in data/raw/.
• Bump TOP_K (sidebar slider) to 8–10 — small k plus large documents often misses the right chunk.
• Try the mmr retriever for broader coverage.

Want a clean rebuild of the vector store

Delete the persisted index:

Remove-Item -Recurse -Force chroma_db

Next run rebuilds it from scratch using the current chunking and embedding settings.

Switching embedding model

Always rebuild the index after changing EMBEDDING_MODEL (or pass a different --embeddings flag to the evaluator). Mixing vectors from different models in the same Chroma collection produces unusable results.

Groq model errors (model has been decommissioned)

Update GROQ_MODEL in utils/config.py to a current model (see https://console.groq.com/docs/deprecations).

License

MIT — see LICENSE for details.

About

Modular RAG system focused on correctness, grounding, and debuggability. Built with LangChain, ChromaDB, HuggingFace embeddings, and the Groq LLM API. Comes with a Streamlit UI and an evaluation harness so you can measure changes instead of guessing.