n8n-nodes-agentic-rag-supabase

Agentic RAG System with Supabase Integration

An advanced Retrieval-Augmented Generation (RAG) system that uses autonomous AI agents to enhance traditional RAG with dynamic query refinement, multi-step reasoning, and tool integration, fully automated via n8n.

🚀 Features

• Agentic Workflow: Autonomous agents that can refine queries and improve results iteratively
• Multi-step Reasoning: Up to 3 iterations of query refinement for better answers
• Supabase Integration: Uses pgvector for efficient vector storage and similarity search
• n8n Automation: Complete workflow automation with webhook endpoints
• Document Support: Handles PDF and TXT files with intelligent parsing
• Quality Evaluation: Automatic answer evaluation with scoring and feedback
• Custom n8n Node: AgenticRAGSupabase node for seamless integration

📁 Project Structure

rag/
├── data/                    # Raw documents (PDF, TXT)
├── vector_store/           # ChromaDB storage
├── n8n_workflows/          # n8n workflow JSON files
├── src/                    # Python source code
│   ├── main.py            # Main orchestrator
│   ├── data_ingestion.py  # Document loading and indexing
│   ├── retriever_tool.py  # Document retrieval tool
│   ├── agent_logic.py     # Agentic workflow logic
│   └── evaluation.py      # Answer quality evaluation
├── nodes/                  # Custom n8n node
├── credentials/           # n8n credentials
├── requirements.txt       # Python dependencies
├── .env                  # Environment configuration
└── README.md             # This file

🛠️ Setup Instructions

1. Install Python Dependencies

cd rag
pip install -r requirements.txt

2. Configure Environment Variables

Edit the .env file with your API keys:

# Required
OPENAI_API_KEY=your_openai_api_key_here
SUPABASE_URL=your_supabase_project_url
SUPABASE_ANON_KEY=your_supabase_anon_key

# Optional
HUGGINGFACE_API_KEY=your_huggingface_api_key_here
N8N_HOST=http://localhost:5678
N8N_API_KEY=your_n8n_api_key_here

3. Set Up Supabase

• Enable the pgvector extension in your Supabase project
• Run the setup SQL to create the required table and function:

-- Enable pgvector extension
CREATE EXTENSION IF NOT EXISTS vector;

-- Create documents table
CREATE TABLE IF NOT EXISTS rag_documents (
  id bigserial primary key,
  content text,
  metadata jsonb,
  embedding vector(384)
);

-- Create search function
CREATE OR REPLACE FUNCTION match_documents (
  query_embedding vector(384),
  match_threshold float,
  match_count int
)
RETURNS table (
  id bigint,
  content text,
  similarity float
)
LANGUAGE sql STABLE
AS $$
  select
    rag_documents.id,
    rag_documents.content,
    1 - (rag_documents.embedding <=> query_embedding) as similarity
  from rag_documents
  where 1 - (rag_documents.embedding <=> query_embedding) > match_threshold
  order by similarity desc
  limit match_count;
$$;

4. Prepare Documents

Place your PDF and TXT files in the data/ directory:

mkdir -p data
# Copy your documents to the data/ folder

5. Ingest Documents

Run the data ingestion to index your documents:

python src/data_ingestion.py

6. Test the System

Test with a single query:

python src/main.py --query "What is the compliance process?"

Or run in interactive mode:

python src/main.py --interactive

🔧 n8n Integration

Install Custom Node

• Build the custom node:

cd rag
npm install
npm run build

• Link the node to your n8n installation:

npm link
cd /path/to/your/n8n
npm link n8n-nodes-agentic-rag-supabase

• Restart n8n to load the new node

Import Workflow

• Open n8n web interface
• Import the workflow from n8n_workflows/agentic_rag_workflow.json
• Configure credentials for the AgenticRAGSupabase node
• Activate the workflow

Usage via Webhook

Send POST requests to the n8n webhook endpoint:

curl -X POST http://localhost:5678/webhook/agentic-rag \
  -H "Content-Type: application/json" \
  -d '{"query": "What is the compliance process for Northwind Health Plus?"}'

📊 System Workflow

• Document Ingestion: Load documents from data/, split into chunks, store embeddings in ChromaDB
• Query Processing: Agent receives query and starts iterative process
• Retrieval: Semantic search for relevant documents
• Generation: LLM generates answer using retrieved context
• Evaluation: Answer quality assessment with scoring
• Refinement: If needed, refine query and repeat (up to 3 iterations)
• Response: Return best answer with quality metrics

🎯 Key Features

• Dynamic Query Rewriting: Automatically improves queries based on evaluation feedback
• Multi-iteration Processing: Up to 3 attempts to find the best answer
• Quality Scoring: Comprehensive evaluation on relevance, groundedness, completeness, clarity, and accuracy
• Extensible Architecture: Easy to add new tools and capabilities
• Production Ready: Full n8n integration for scalable deployment

🔍 Usage Examples

Python Direct Usage

from src.agent_logic import AgenticRAGAgent

agent = AgenticRAGAgent()
result = agent.process_query("What are the safety protocols?")
print(result['final_answer'])

n8n Webhook Usage

const response = await fetch('http://localhost:5678/webhook/agentic-rag', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ query: 'What is the compliance process?' })
});

const result = await response.json();
console.log(result.answer);

🚨 Troubleshooting

• No documents found: Ensure documents are in the data/ directory and run data ingestion
• API errors: Check your API keys in the .env file
• ChromaDB issues: Delete the vector_store/ directory and re-run data ingestion
• n8n node not appearing: Ensure the node is properly built and linked

📈 Performance Tips

• Use specific queries for better retrieval results
• Regularly update your document collection
• Monitor evaluation scores to identify areas for improvement
• Adjust similarity thresholds based on your use case

🤝 Contributing

This system is designed to be extensible. You can:

• Add new document loaders for different file types
• Implement additional evaluation metrics
• Create new retrieval strategies
• Extend the n8n node with more operations

📄 License

MIT License - see LICENSE file for details.