n8n -RAG

This MCP server wraps an n8n-driven workflow generator that uses Retrieval-Augmented Generation (RAG) to produce importable n8n workflows from plain English prompts or structured JSON prompts. It supports multiple providers/endpoints for model inference and integrates LangWatch for observability of RAG requests and responses. Use the UI to describe the workflow you want in natural language or provide a JSON schema with fields like goal, triggers, and integrations. The backend retrieves relevant context chunks, builds a tailored prompt, calls your chosen provider, and returns a ready-to-import n8n workflow JSON.

Prerequisites: a machine with Docker and Docker Compose installed, and access to a provider API key (OpenAI, Anthropic, Gemini, etc.). Optional: a LangWatch API key for monitoring and a Redis instance for caching.

1. Clone the repository and navigate to the project directory.
2. Copy the example environment file and populate it with your settings:
   • LANGWATCH_API_KEY (optional)
   • REDIS_URL (optional; e.g., redis://localhost:6379/0)
   • RUN_INDEX_ON_START (optional; default may be true/false in your setup)
3. Build and start the containers: docker compose up -d --build
4. Check logs to ensure the app started correctly: docker compose logs -f app
5. Open the UI at http://localhost:8000/ui and start generating workflows.

Indexing data (optional but recommended):

• One-time local indexing: docker compose run --rm app python chunk_all.py docker compose run --rm app python build_chroma.py

Reindex on demand:

• curl -X POST "http://localhost:8000/reindex" -H "X-Admin-Token: your-admin-token"

Tips: Ensure your API keys and tokens are kept out of code and stored in the .env file or your environment. If you run into indexing issues, verify that Redis and Chroma dependencies are available and that REDIS_URL, CHROMA settings, and provider keys are correctly configured. For LangWatch monitoring, provide LANGWATCH_API_KEY to enable automatic logging of RAG requests and responses. If you encounter Docker-related problems, confirm Docker and Docker Compose versions and network access. The server exposes endpoints like GET /health, POST /generate, and POST /refine_prompt; use /ui for a friendlier interface. If you plan to deploy publicly, consider securing endpoints behind a reverse proxy and enabling authentication tokens.