Unanswered Questions MCP Server

MCP server that tracks questions a RAG chatbot can't answer, clusters them by semantic similarity, and suggests what documentation to add.

Built to plug into a multi-tenant RAG chatbot in production. When the chatbot gives a low-confidence answer, it logs the question here. Run pattern analysis periodically to find out what docs are missing.

Article: Build an MCP Server That Finds Your RAG Chatbot's Blind Spots

How It Works

User question → RAG chatbot → low confidence?
                                    │
                    log_unanswered_question
                          │
                     SQLite + embedding
                          │
              get_question_patterns (weekly)
                          │
                 clusters by similarity
                          │
               suggest_documents → write docs → mark_resolved

4 tools exposed over MCP:

Related MCP server: claude-rag-mcp

Quick Start

uv sync
cp .env.example .env   # add your OPENAI_API_KEY
python test_server.py # Run the test suite (needs API key)
python server.py # Start the MCP server

Claude Desktop config

{
  "mcpServers": {
    "unanswered-questions": {
      "command": "python",
      "args": ["/path/to/unanswered-questions-mcp/server.py"]
    }
  }
}

Why It's Built This Way

SQLite over a vector database — Batch analysis, not real-time retrieval. Zero-config and handles 10K+ questions fine.

Greedy cosine-similarity clustering — Embeddings via text-embedding-3-small, cosine similarity matrix, then greedy assignment above a configurable threshold.

Multi-tenant from day one — Every operation takes an optional tenant_id. Matches the production RAG chatbot it plugs into.

Limitations

• Batch, not real-time — Pattern analysis is meant to run periodically, not as a streaming pipeline.

• Greedy clustering is order-dependent — Results can vary slightly across runs. Fine for broad patterns, not precise categorization.

• No auth — Relies on the MCP client handling access. Add authentication if exposing over HTTP.