RAG Engine

Turn-key Knowledge Base for AI Agents

Fully managed RAG-as-a-service with vector storage, document chunking, and semantic retrieval — exposed as an MCP server. Upload PDFs, DOCX, images, and more. Your agents search your knowledge base with natural language.

What it does

RAG Engine is a fully managed knowledge base pipeline for AI agents. Upload documents through the dashboard or API, and they are automatically parsed, chunked, embedded, and indexed in a vector database. Your agents then search across this knowledge base using natural language, getting back the most relevant passages with citations.

RAG Engine is exposed as a built-in MCP server through MCP Gateway Pro. When your agent calls rag-engine/knowledge_query, it runs a semantic search and returns matching document chunks. No infrastructure to manage — just upload and search.

How It Works

1
Upload
PDF, DOCX, images...
2
Parse
Extract text
3
Chunk
Split into passages
4
Embed
Vector embeddings
5
Index
pgvector store
6
Search
Semantic retrieval
Built on
Durable Storage Job Queue Vector Embeddings Vector Database OCR Engine

Batch upload with the CLI

The AppXen CLI is the fastest way to load documents. Point it at a directory and it uploads everything, with progress tracking and status polling built in.

$ appxen ingest ./docs/ --recursive

Supported Formats

Documents

PDF DOCX HTML Markdown CSV JSON Plain text

Images (via OCR)

PNG JPEG TIFF BMP

Text extracted via OCR

Key Features

Drag-and-Drop Upload

Upload documents through the dashboard with drag-and-drop or paste text directly. Track ingestion status in real time.

Semantic Search

Vector similarity search powered by pgvector. Adjustable top-k results.

MCP Integration

Exposed as a built-in MCP server with 5 tools. Any agent connected to your gateway can query your knowledge base.

Dashboard

Overview stats, source management, search playground with query history, and ingestion monitoring. All from the console.

Multi-Format Parsing

PDF, DOCX, HTML, Markdown, CSV, JSON, plain text, and images via OCR. Automatic format detection.

Async Ingestion

File uploads are queued and processed in the background. Poll for status or check the dashboard. No request timeouts for large files.

MCP Tools

RAG Engine exposes 5 tools through the gateway. Any AI agent connected to your gateway endpoint can use these tools directly.

knowledge_query

Search your knowledge base using natural language. Returns the most relevant document chunks with citations.

knowledge_ingest

Add a document to your knowledge base. Provide text directly or base64-encoded file content for binary formats.

knowledge_list_sources

List all indexed documents in your knowledge base. Filter by status (queued, processing, ready, failed).

knowledge_delete_source

Delete a document and all its chunks from the knowledge base.

knowledge_get_chunk

Get a specific chunk by ID for citation follow-up or context expansion.

Example: Search Your Knowledge Base

# Agent searches the knowledge base through Gateway
POST /mcp
{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "rag-engine/knowledge_query",
    "arguments": {
      "query": "What is our refund policy?",
      "top_k": 3
    }
  }
}

Storage vs RAG Engine

MCP Gateway Pro includes both raw file storage and the RAG Engine knowledge base. They serve different purposes:

Storage

Raw file storage for AI agents. Files stay as-is.

  • - Agents read files verbatim via MCP tools
  • - Good for reference documents agents access directly
  • - Images, videos, code files, any format

RAG Engine

Knowledge base pipeline. Documents are parsed, chunked, embedded, and indexed.

  • - Agents run semantic search across content
  • - Good for large document collections
  • - Find relevant info without reading entire files

Pricing

RAG storage $1.00/GB
API request $0.005
Minimum No minimum

API requests billed through MCP Gateway Pro.

Specs

Embedding dimensions 1024
Max file size 100 MB
Formats 10+
MCP tools 5

Dashboard

Overview — stats & recent activity
Sources — upload & manage docs
Search — query playground
Analytics — coming soon

Ready to get started?

Deploy RAG Engine in minutes. Usage-based pricing, no upfront commitment.