|
| 1 | +# **Building an Intelligent Documentation Assistant with MongoDB-RAG** |
| 2 | + |
| 3 | +### *by Michael Lynn, Developer Advocate @ MongoDB* |
| 4 | +📌 [GitHub](https://github.com/mrlynn) | 🛠️ [MongoDB-RAG Docs](https://mongodb.github.io/mongo-rag/) |
| 5 | + |
| 6 | +--- |
| 7 | + |
| 8 | +## **📖 TL;DR** |
| 9 | +Ever wished your documentation could just *answer questions* directly instead of forcing users to sift through endless pages? That’s exactly what we built with the **MongoDB-RAG Documentation Assistant**. In this article, I’ll walk you through the **why, what, and how** of building a chatbot that retrieves precise, relevant information from MongoDB-RAG’s own documentation. |
| 10 | + |
| 11 | +### **🤔 Why Build a Documentation Assistant?** |
| 12 | +Traditional documentation search is useful, but it often leaves users with *more questions than answers*. Developers need to read through entire pages, infer context, and piece together solutions. Instead, we wanted something: |
| 13 | + |
| 14 | +✅ **Conversational** – Answers questions in natural language |
| 15 | +✅ **Context-aware** – Finds relevant documentation snippets instead of just keywords |
| 16 | +✅ **Fast & Accurate** – Uses vector search to surface precise answers |
| 17 | +✅ **Transparent** – Links to original sources so users can verify answers |
| 18 | +✅ **Scalable** – Handles multiple LLM providers, including **OpenAI** and **Ollama** |
| 19 | + |
| 20 | +Our solution? **A chatbot powered by MongoDB-RAG**, showcasing exactly what our tool was built for: **retrieval-augmented generation (RAG)** using **MongoDB Atlas Vector Search**. |
| 21 | + |
| 22 | +--- |
| 23 | + |
| 24 | +## **🛠️ How We Built It** |
| 25 | +We structured the assistant around four core components: |
| 26 | + |
| 27 | +### **1️⃣ Document Ingestion** |
| 28 | +To make documentation *searchable*, we need to process it into vector embeddings. We use **semantic chunking** to break long docs into meaningful pieces before ingestion. |
| 29 | + |
| 30 | +```javascript |
| 31 | +const chunker = new Chunker({ |
| 32 | + strategy: 'semantic', |
| 33 | + maxChunkSize: 500, |
| 34 | + overlap: 50 |
| 35 | +}); |
| 36 | + |
| 37 | +const documents = await loadMarkdownFiles('./docs'); |
| 38 | +const chunks = await Promise.all( |
| 39 | + documents.map(doc => chunker.chunkDocument(doc)) |
| 40 | +); |
| 41 | + |
| 42 | +await rag.ingestBatch(chunks.flat()); |
| 43 | +``` |
| 44 | + |
| 45 | +> 📝 **Why Semantic Chunking?** Instead of blindly splitting text, we preserve contextual integrity by overlapping related sections. |
| 46 | +
|
| 47 | +--- |
| 48 | + |
| 49 | +### **2️⃣ Vector Search with MongoDB Atlas** |
| 50 | +Once ingested, we use **MongoDB Atlas Vector Search** to find the most relevant documentation snippets based on a user’s query. |
| 51 | + |
| 52 | +```javascript |
| 53 | +const searchResults = await rag.search(query, { |
| 54 | + maxResults: 6, |
| 55 | + filter: { 'metadata.type': 'documentation' } |
| 56 | +}); |
| 57 | +``` |
| 58 | + |
| 59 | +MongoDB’s **$vectorSearch** operator ensures we retrieve the closest matching content, ranked by relevance. |
| 60 | + |
| 61 | +--- |
| 62 | + |
| 63 | +### **3️⃣ Streaming Responses for a Real Chat Experience** |
| 64 | +To improve user experience, we stream responses incrementally as they’re generated. |
| 65 | + |
| 66 | +```javascript |
| 67 | +router.post('/chat', async (req, res) => { |
| 68 | + const { query, history = [], stream = true } = req.body; |
| 69 | + |
| 70 | + const context = await ragService.search(query); |
| 71 | + |
| 72 | + if (stream) { |
| 73 | + res.writeHead(200, { |
| 74 | + 'Content-Type': 'text/event-stream', |
| 75 | + 'Cache-Control': 'no-cache', |
| 76 | + 'Connection': 'keep-alive' |
| 77 | + }); |
| 78 | + |
| 79 | + await llmService.generateResponse(query, context, history, res); |
| 80 | + } else { |
| 81 | + const answer = await llmService.generateResponse(query, context, history); |
| 82 | + res.json({ answer, sources: context }); |
| 83 | + } |
| 84 | +}); |
| 85 | +``` |
| 86 | + |
| 87 | +With this approach: |
| 88 | +- Responses appear **in real-time** instead of waiting for full generation 🚀 |
| 89 | +- Developers can get **partial answers** quickly while longer responses load |
| 90 | + |
| 91 | +--- |
| 92 | + |
| 93 | +### **4️⃣ Multi-Provider LLM Support** |
| 94 | +The assistant supports **multiple embedding providers**, including OpenAI and **self-hosted Ollama**. |
| 95 | + |
| 96 | +```javascript |
| 97 | +const config = { |
| 98 | + embedding: { |
| 99 | + provider: process.env.EMBEDDING_PROVIDER || 'openai', |
| 100 | + model: process.env.EMBEDDING_MODEL || 'text-embedding-3-small', |
| 101 | + baseUrl: process.env.OLLAMA_BASE_URL // For local deployment |
| 102 | + } |
| 103 | +}; |
| 104 | +``` |
| 105 | + |
| 106 | +This allows users to **switch providers** easily, optimizing for performance, privacy, or cost. |
| 107 | + |
| 108 | +--- |
| 109 | + |
| 110 | +## **💡 Key Features** |
| 111 | + |
| 112 | +### 🔍 **Real-time Context Retrieval** |
| 113 | +Instead of guessing, the chatbot **searches first** and then generates answers. |
| 114 | + |
| 115 | +### 🔗 **Source Attribution** |
| 116 | +Each response includes a **link to the documentation**, letting users verify answers. |
| 117 | + |
| 118 | +### ⏳ **Streaming Responses** |
| 119 | +No waiting! Answers **generate in real-time**, improving responsiveness. |
| 120 | + |
| 121 | +### ⚙️ **Multi-Provider LLM Support** |
| 122 | +Deploy with **OpenAI for scale** or **Ollama for private, local hosting**. |
| 123 | + |
| 124 | +### 🤖 **Fallback Handling** |
| 125 | +If documentation doesn’t contain an answer, the chatbot **transparently explains the limitation** instead of fabricating responses. |
| 126 | + |
| 127 | +--- |
| 128 | + |
| 129 | +## **🚀 Try It Yourself** |
| 130 | +Want to build a **MongoDB-RAG-powered assistant**? Here’s how to get started: |
| 131 | + |
| 132 | +### **1️⃣ Install MongoDB-RAG** |
| 133 | +```bash |
| 134 | +npm install mongodb-rag |
| 135 | +``` |
| 136 | + |
| 137 | +### **2️⃣ Configure Your Environment** |
| 138 | +```env |
| 139 | +MONGODB_URI=your_atlas_connection_string |
| 140 | +EMBEDDING_PROVIDER=openai |
| 141 | +EMBEDDING_API_KEY=your_api_key |
| 142 | +EMBEDDING_MODEL=text-embedding-3-small |
| 143 | +``` |
| 144 | + |
| 145 | +### **3️⃣ Initialize the Chatbot** |
| 146 | +```javascript |
| 147 | +import { MongoRAG } from 'mongodb-rag'; |
| 148 | +import express from 'express'; |
| 149 | + |
| 150 | +const rag = new MongoRAG(config); |
| 151 | +const app = express(); |
| 152 | + |
| 153 | +app.post('/api/chat', async (req, res) => { |
| 154 | + const { query } = req.body; |
| 155 | + const results = await rag.search(query); |
| 156 | + res.json({ answer: results }); |
| 157 | +}); |
| 158 | +``` |
| 159 | + |
| 160 | +--- |
| 161 | + |
| 162 | +## **🌩️ Production Considerations** |
| 163 | +### **Where to Host?** |
| 164 | +We deployed our assistant on **Vercel** for: |
| 165 | +- **Serverless scalability** |
| 166 | +- **Fast global CDN** |
| 167 | +- **Easy Git-based deployments** |
| 168 | + |
| 169 | +### **Which LLM for Production?** |
| 170 | +- **OpenAI** – Best for reliability & speed |
| 171 | +- **Ollama** – Best for **privacy-first** self-hosted setups |
| 172 | + |
| 173 | +```env |
| 174 | +EMBEDDING_PROVIDER=openai |
| 175 | +EMBEDDING_MODEL=text-embedding-3-small |
| 176 | +``` |
| 177 | + |
| 178 | +--- |
| 179 | + |
| 180 | +## **🔮 What’s Next?** |
| 181 | +Future improvements include: |
| 182 | +- **Better query reformulation** to improve retrieval accuracy |
| 183 | +- **User feedback integration** to refine responses over time |
| 184 | +- **Conversation memory** for context-aware follow-ups |
| 185 | + |
| 186 | +--- |
| 187 | + |
| 188 | +## **🎬 Conclusion** |
| 189 | +By combining **MongoDB Atlas Vector Search** with **modern LLMs**, we built an assistant that **transforms documentation into an interactive experience**. |
| 190 | + |
| 191 | +Try it out in our docs, and let us know what you think! 🚀 |
| 192 | + |
| 193 | +### 🔗 **Resources** |
| 194 | +📘 [MongoDB-RAG Docs](https://mongodb.github.io/mongo-rag/) |
| 195 | +🔗 [GitHub Repository](https://github.com/mongodb-developer/mongodb-rag) |
| 196 | +📦 [NPM Package](https://www.npmjs.com/package/mongodb-rag) |
0 commit comments