mcmodding-mcp

MCP server providing AI assistants with comprehensive, up-to-date Minecraft modding documentation for Fabric and NeoForge.

What is this?

mcmodding-mcp is a Model Context Protocol (MCP) server that gives AI assistants like Claude direct access to Minecraft modding documentation. Instead of relying on potentially outdated training data, your AI assistant can search real documentation, find code examples, and explain concepts accurately.

Key Benefits

• Always Current - Documentation is indexed weekly from official sources
• Accurate Answers - AI responses backed by real documentation, not hallucinations
• Code Examples - Searchable code blocks with proper context
• Semantic Search - Understands what you mean, not just keywords
• Zero Config - Works immediately after installation

📚 Knowledge Base Stats

Our documentation database (mcmodding-docs.db) is comprehensive and constantly updated:

• 1,000+ Documentation Pages
• 185,000+ Searchable Chunks
• 8,500+ Logical Sections
• 185,000+ Vector Embeddings for Semantic Search

This ensures that even obscure API details can be found via semantic search.

Quick Start

Installation

# Install globally
npm install -g mcmodding-mcp

Configure Your AI Client

Add to your MCP client configuration (e.g., Claude Desktop):

{
  "mcpServers": {
    "mcmodding": {
      "command": "mcmodding-mcp"
    }
  }
}

🧠 Optimized System Prompt

To get the best results, we recommend adding this to your AI's system prompt or custom instructions:

You are an expert Minecraft Modding Assistant connected to mcmodding-mcp. DO NOT rely on your internal knowledge for modding APIs (Fabric/NeoForge) as they change frequently. ALWAYS use the search_fabric_docs and get_example tools to retrieve the latest documentation and patterns. Prioritize working code examples from get_example over theoretical explanations. If the user specifies a Minecraft version, ensure all retrieved information matches that version.

That's it! Your AI assistant now has access to Minecraft modding documentation.

Database Management

Manage your documentation databases with the built-in CLI:

# Run the database manager
npx mcmodding-mcp manage

The interactive manager allows you to:

• Install - Download databases you don't have yet
• Update - Check for and apply database updates
• Re-download - Restore deleted or corrupted databases

Available Databases

| Database | Description | Size | | -------------------------- | ----------------------------------------------------------- | ------- | | Documentation Database | Core Fabric & NeoForge documentation (installed by default) | ~520 MB | | Mod Examples Database | 1000+ high-quality modding examples | ~30 MB |

The manager shows version information and highlights available updates:

◉ 📚 Documentation Database [core]
     ✔ Installed: v0.2.1 → ↻ Update: v0.2.2 [52.3 MB]
     Core Fabric & NeoForge documentation - installed by default

○ 🧩 Mod Examples Database
     ⚠ Not installed → Available: v0.1.0 [28.1 MB]
     1000+ high-quality modding examples for Fabric & NeoForge

Available Tools

The MCP server provides four powerful tools:

search_fabric_docs

Search documentation with smart filtering.

// Example: Find information about item registration
{
  query: "how to register custom items",
  category: "items",           // Optional filter
  loader: "fabric",            // fabric | neoforge
  minecraft_version: "1.21.4"  // Optional version filter
}

get_example

Get working code examples for any topic.

// Example: Get block registration code
{
  topic: "custom block with block entity",
  language: "java",
  loader: "fabric"
}

explain_fabric_concept

Get detailed explanations of modding concepts with related resources.

// Example: Understand mixins
{
  concept: 'mixins';
}

get_minecraft_version

Get current Minecraft version information.

// Get latest version
{
  type: 'latest';
}

// Get all indexed versions
{
  type: 'all';
}

Features

Hybrid Search Engine

Combines multiple search strategies for best results:

| Strategy | Purpose | | ----------------------- | --------------------------------------- | | FTS5 Full-Text | Fast keyword matching with ranking | | Semantic Embeddings | Understanding meaning and context | | Section Search | Finding relevant documentation sections | | Code Search | Locating specific code patterns |

Auto-Updates

The database automatically checks for updates on startup:

• Compares local version with GitHub releases
• Downloads new versions with hash verification
• Creates backups before updating
• Non-blocking - server starts immediately

Documentation Sources

Currently indexes:

• wiki.fabricmc.net - Fabric Wiki (226+ pages)
• docs.fabricmc.net - Official Fabric Docs (266+ pages)
• docs.neoforged.net - NeoForge Docs (512+ pages)

For Developers

Development Setup

# Clone repository
git clone https://github.com/OGMatrix/mcmodding-mcp.git
cd mcmodding-mcp

# Install dependencies
npm install

# Run in development mode
npm run dev

Build Commands

# Development
npm run dev              # Watch mode with hot reload
npm run typecheck        # TypeScript type checking
npm run lint             # ESLint
npm run test             # Run tests
npm run format           # Prettier formatting

# Production
npm run build            # Build TypeScript
npm run build:prod       # Build with fresh documentation index
npm run index-docs       # Index documentation with embeddings

# Database Management
npx mcmodding-mcp manage # Interactive database installer/updater

Project Structure

mcmodding-mcp/
├── src/
│   ├── index.ts              # MCP server entry point
│   ├── db-versioning.ts      # Auto-update system
│   ├── indexer/
│   │   ├── crawler.ts        # Documentation crawler
│   │   ├── chunker.ts        # Text chunking
│   │   ├── embeddings.ts     # Semantic embeddings
│   │   ├── store.ts          # SQLite database
│   │   └── sitemap.ts        # Sitemap parsing
│   ├── services/
│   │   ├── search-service.ts # Search logic
│   │   └── concept-service.ts # Concept explanations
│   └── tools/
│       ├── searchDocs.ts     # search_fabric_docs handler
│       ├── getExample.ts     # get_example handler
│       └── explainConcept.ts # explain_fabric_concept handler
├── scripts/
│   └── index-docs.ts         # Documentation indexing script
├── data/
│   ├── mcmodding-docs.db     # SQLite database
│   └── db-manifest.json      # Version manifest
└── dist/                     # Compiled JavaScript

Database Schema

-- Documents: Full documentation pages
CREATE TABLE documents (
  id INTEGER PRIMARY KEY,
  url TEXT UNIQUE NOT NULL,
  title TEXT NOT NULL,
  content TEXT NOT NULL,
  category TEXT NOT NULL,
  loader TEXT NOT NULL,          -- fabric | neoforge | shared
  minecraft_version TEXT,
  hash TEXT NOT NULL             -- For change detection
);

-- Chunks: Searchable content units
CREATE TABLE chunks (
  id TEXT PRIMARY KEY,
  document_id INTEGER NOT NULL,
  chunk_type TEXT NOT NULL,      -- title | section | code | full
  content TEXT NOT NULL,
  section_heading TEXT,
  code_language TEXT,
  word_count INTEGER,
  has_code BOOLEAN
);

-- Embeddings: Semantic search vectors
CREATE TABLE embeddings (
  chunk_id TEXT PRIMARY KEY,
  embedding BLOB NOT NULL,       -- 384-dim Float32Array
  dimension INTEGER NOT NULL,
  model TEXT NOT NULL            -- Xenova/all-MiniLM-L6-v2
);

-- FTS5 indexes for fast text search
CREATE VIRTUAL TABLE documents_fts USING fts5(...);
CREATE VIRTUAL TABLE chunks_fts USING fts5(...);

Release Workflow

This project uses release-please for automated releases.

Branch Strategy

| Branch | Purpose | | ------ | ------------------- | | dev | Active development | | prod | Production releases |

How It Works

1. Push commits to dev using conventional commits
2. Release-please maintains a Release PR (dev → prod)
3. When merged, automatic release: npm publish + GitHub release + database upload
4. Changes sync back to dev

See RELEASE_WORKFLOW.md for complete details.

Configuration

Environment Variables

| Variable | Description | Default | | ----------------- | ----------------------- | -------------------------- | | DB_PATH | Custom database path | ./data/mcmodding-docs.db | | GITHUB_REPO_URL | Custom repo for updates | Auto-detected | | MCP_DEBUG | Enable debug logging | false |

Disabling Auto-Updates

Set DB_PATH to a custom location to manage updates manually:

DB_PATH=/path/to/my/database.db mcmodding-mcp

Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

Quick Contribution Guide

1. Fork the repository
2. Create a feature branch from dev
3. Make changes with conventional commits
4. Submit a PR to dev

License

MIT License - see LICENSE for details.

Changelog

See CHANGELOG.md for a detailed history of changes and releases.

Acknowledgments

• Fabric Documentation - Official Fabric documentation
• Fabric Wiki - Community wiki
• Model Context Protocol - MCP specification
• Transformers.js - Local ML embeddings
• better-sqlite3 - Fast SQLite bindings