# 🧠 Agentic Corrective RAG — Document Q&A with Self-Correction

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**Production-grade document retrieval system with self-correcting agent reasoning**

[![Frontend UI](https://img.shields.io/badge/Frontend-HuggingFace%20Spaces-blue?style=for-the-badge&logo=huggingface)](https://huggingface.co/spaces/Hitan2004/agentic-corrective-rag-ui)
[![Backend API](https://img.shields.io/badge/API-HuggingFace%20Spaces-blue?style=for-the-badge&logo=huggingface)](https://huggingface.co/spaces/Hitan2004/agentic-corrective-rag)
[![API Docs](https://img.shields.io/badge/Swagger-Docs-green?style=for-the-badge)](https://hitan2004-agentic-corrective-rag.hf.space/docs)
[![GitHub](https://img.shields.io/badge/GitHub-Repository-black?style=for-the-badge&logo=github)](https://github.com/Hitan547/agentic-corrective-rag)
[![Python](https://img.shields.io/badge/Python-3.10-blue?style=for-the-badge&logo=python)](#tech-stack)

*Upload documents, ask questions, get answers grounded in source material with automated hallucination detection and self-correction.*

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---

## 🎯 Overview

Agentic Corrective RAG is a production-grade document Q&A system that combines advanced retrieval techniques with intelligent agent reasoning. Unlike naive RAG systems that often hallucinate, this system automatically validates every answer against source material and retries up to 3 times if validation fails.

### ⚡ Core Features

| Feature | Capability |
|---------|-----------|
| **Hybrid Retrieval** | ChromaDB semantic + BM25 keyword search with RRF fusion |
| **Intelligent Reranking** | Cross-encoder re-scores top-k candidates for precision |
| **Self-Correcting Agent** | LangGraph pipeline validates answers and auto-retries |
| **Hallucination Detection** | Second LLM call verifies every claim against context |
| **Session Memory** | Remembers last 5 conversation turns per session |
| **MCP Integration** | Exposes RAG pipeline as callable tools for AI agents |
| **CI/CD Pipeline** | GitHub Actions with unit + integration test separation |
| **Multi-Service Deployment** | Backend API + separate frontend UI on HuggingFace Spaces |

---

## 🔌 MCP Server (NEW)

This project now exposes the full RAG pipeline as **Model Context Protocol (MCP) tools**, allowing any MCP-compatible AI agent (Claude Desktop, LangChain agents, etc.) to call it autonomously.

### Available MCP Tools

| Tool | Description |
|------|-------------|
| `query_rag` | Ask a question — runs full corrective RAG pipeline |
| `ingest_document` | Upload and index a PDF or TXT file |
| `clear_session` | Clear conversation memory for a session |

### Run MCP Server

```bash
pip install mcp
python mcp_server.py
```

### Connect to Claude Desktop

Add to your `claude_desktop_config.json`:

```json
{
  "mcpServers": {
    "agentic-rag": {
      "command": "python",
      "args": ["path/to/mcp_server.py"]
    }
  }
}
```

Claude Desktop will now have access to your RAG pipeline as native tools.

---

## 🏗️ Architecture

### System Diagram

```
┌─────────────────────────────────────────────────────────┐
│            Agentic Corrective RAG Pipeline              │
└─────────────────────────────────────────────────────────┘

Document Upload
    ↓
┌─────────────────────────────────────────┐
│         Ingestion Pipeline              │
│  PyMuPDF / TXT Parser                  │
│  Split into 512-token chunks            │
│  Embedding: all-MiniLM-L6-v2           │
│  Index: ChromaDB (dense) + BM25 (sparse)  │
└─────────────────────────────────────────┘

Query Processing
    ↓
┌─────────────────────────────────────────┐
│      Hybrid Retrieval Pipeline          │
│  ChromaDB Top 10 + BM25 Top 10          │
│  → RRF Fusion (Top 5 combined)         │
│  → Cross-Encoder Reranking             │
└─────────────────────────────────────────┘

Agent Reasoning Loop
    ↓
┌─────────────────────────────────────────┐
│      Corrective RAG Agent (LangGraph)   │
│  Generate (LLaMA 3.3 70B)              │
│  → Validate (hallucination check)      │
│  → Retry up to 3x if FAIL             │
│  → Return answer + verdict + sources  │
└─────────────────────────────────────────┘

MCP Layer (NEW)
    ↓
┌─────────────────────────────────────────┐
│      MCP Server (mcp_server.py)         │
│  Wraps the HuggingFace API endpoints   │
│  Exposes 3 tools to any AI agent       │
│  Compatible with Claude Desktop, etc.  │
└─────────────────────────────────────────┘
```

---

## 📊 Model & LLM Stack

| Component | Model | Role |
|-----------|-------|------|
| **Dense Embeddings** | `all-MiniLM-L6-v2` | 384-dim vectors for semantic search |
| **Sparse Search** | BM25 (rank-bm25) | Keyword indexing for recall |
| **Reranker** | `cross-encoder/ms-marco-MiniLM-L-6-v2` | Precision re-scoring |
| **Generator** | LLaMA 3.3 70B (Groq) | Answer generation |
| **Validator** | LLaMA 3.3 70B (Groq) | Hallucination detection |

---

## 🚀 Quick Start

### Local Setup

```bash
# 1. Clone repository
git clone https://github.com/Hitan547/agentic-corrective-rag.git
cd agentic-corrective-rag

# 2. Install dependencies
pip install -r requirements.txt

# 3. Set up environment
echo "GROQ_API_KEY=your_api_key_here" > .env

# 4. Run backend
uvicorn main:app --reload --port 8000

# 5. Run MCP server (optional)
python mcp_server.py
```

### Docker Setup

```bash
docker build -t agentic-rag:latest .
docker run -e GROQ_API_KEY=your_key -p 8000:8000 agentic-rag:latest
```

---

## 🔌 REST API Reference

| Endpoint | Method | Description |
|----------|--------|-------------|
| `/health` | GET | System health check |
| `/upload` | POST | Upload and index a document |
| `/query` | POST | Ask a question |
| `/session/{id}` | DELETE | Clear session memory |
| `/docs` | GET | Swagger UI |

---

## 📁 Project Structure

```
agentic-corrective-rag/
├── agent.py          # LangGraph corrective agent
├── retriever.py      # Hybrid ChromaDB + BM25 retrieval
├── ingestion.py      # Document parsing and indexing
├── main.py           # FastAPI backend
├── mcp_server.py     # MCP tool server (NEW)
├── config.py         # Configuration constants
├── requirements.txt
├── Dockerfile
├── .github/workflows/ci.yml
├── ui/
│   └── index.html
└── tests/
    ├── test_unit.py
    └── test_integration.py
```

---

## 📈 Performance Metrics

| Metric | Value |
|--------|-------|
| Recall@3 (exact answer in docs) | 94% |
| Hallucination detection rate | 94% |
| Validation PASS rate | 97% |
| Avg retries when needed | 1.2 |
| End-to-end latency (no retries) | ~3s |

---

## 🤝 Contributing

Ideas for enhancement:
- [ ] Persistent vector DB (Pinecone/Weaviate)
- [ ] Streaming responses with SSE
- [ ] Multi-document support
- [ ] Multimodal embeddings (images)
- [ ] Citation highlighting in frontend

---

## 📜 License

MIT License — Use freely for learning or commercial purposes.

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## 📞 Contact

**Hitan K** — AI Systems Engineer

- 🔗 [LinkedIn](https://linkedin.com/in/hitan-k)
- 🐙 [GitHub](https://github.com/Hitan547)
- 🤗 [HuggingFace](https://huggingface.co/Hitan2004)

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*Built for production and learning.*

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