GameCodex

Your AI forgets everything mid-project. Give it permanent game development knowledge.

GameCodex is a knowledge layer for AI coding assistants. It provides 147+ curated game development docs — design patterns, architecture guides, engine-specific implementation details — delivered through MCP so your AI assistant never loses context on how to build games.

Works with Claude Code, Claude Desktop, Cursor, Windsurf, Cline, and any MCP-compatible tool.

The Problem

Every game dev using AI hits the same wall: your assistant starts strong, then forgets your architecture mid-session. It suggests deprecated APIs. It doesn't know the difference between a state machine and a behavior tree. It writes Unity 5 code when you're on Unity 6.

GameCodex solves this by giving your AI a persistent, searchable knowledge base of curated game dev expertise — not raw docs, but structured implementation guidance that actually helps you build.

What's Inside

147+ docs. 4.8MB+ of curated knowledge. Zero external dependencies.

Quick Start

npx gamecodex

That's it. No install required. Add it to your MCP config and your AI has instant game dev knowledge.

Claude Code

claude mcp add gamedev -- npx -y gamecodex

Claude Desktop / Cursor / Windsurf / Cline

Add to your MCP config file:

{
  "mcpServers": {
    "gamedev": {
      "command": "npx",
      "args": ["-y", "gamecodex"]
    }
  }
}

Config file locations:

• Claude Desktop: claude_desktop_config.json
• Cursor: .cursor/mcp.json
• Windsurf: ~/.windsurf/mcp.json
• Cline: VS Code settings → Cline MCP Servers

Engine Modules

GameCodex uses a modular architecture. Core knowledge (design, patterns, algorithms) is always available. Engine-specific modules add implementation guides for your stack.

Modules are auto-discovered. To filter which modules load:

{
  "env": {
    "GAMEDEV_MODULES": "monogame-arch,godot-arch"
  }
}

Without GAMEDEV_MODULES, all available modules load automatically.

MCP Tools

Context-Efficient by Design

Unlike tool-heavy MCP servers that dump 50K+ tokens of schemas into your context window, GameCodex is built for precision:

• Section extraction — get_doc("G64", section: "Knockback") returns just the knockback section, not the full 52KB doc
• maxLength param — Cap any response to fit your context budget
• 10 focused tools — Minimal schema overhead, maximum utility. Compare to Godot MCP servers with 95+ tools burning half your context on schema alone
• stdio transport — No network exposure, no attack surface (MCP security is a real concern)

Free vs Pro

The server works fully out of the box with a generous free tier.

Pro unlocks engine-specific implementation guides — the stuff that turns "I know game design theory" into "here's exactly how to build it in Godot/MonoGame/Unity."

Get a Pro license → gamecodex.lemonsqueezy.com

License Setup

gamecodex setup

Interactive setup walks you through activation. Or add your key to the MCP config:

{
  "env": {
    "GAMECODEX_LICENSE": "your-license-key"
  }
}

The server validates on startup, caches for 24h, and gracefully falls back to free tier if anything goes wrong. It never crashes.

What Makes This Different

There are 14,000+ MCP servers out there. Here's why this one matters for game dev:

• Knowledge, not integration. Godot-MCP, Unity-MCP, and Unreal-MCP give your AI buttons to press in the editor. This gives your AI understanding of how to architect and build games. They're complementary — use both.
• Cross-engine. One server, multiple engines. Learn a pattern once in core theory, then get the engine-specific implementation. compare_engines("camera") shows you how Godot and MonoGame each handle it. No need to install separate MCPs per engine.
• Curated, not scraped. Every doc is hand-written with AI code generation in mind — typed examples, anti-pattern warnings, decision trees, and "when to use" guidance. This isn't a docs mirror.
• Secure by design. stdio-only transport — no network exposure, no open ports, no attack surface. While 7,000+ MCP servers sit exposed on the internet, this runs entirely local.
• Grows with you. New docs and engines added continuously. Your AI gets smarter over time without you changing anything.

Genre Coverage

The genre_lookup tool maps any genre to its required systems with implementation priorities:

Platformer · Metroidvania · Roguelike · Tower Defense · Survival · RPG · Bullet Hell · Top-Down Shooter · Side-Scrolling · Fighting · Puzzle

Each genre profile includes: required systems, optional enhancements, suggested doc reading order, and a starter checklist.

Development

git clone https://gitlab.com/shawn-benson/GameCodex.git
cd GameCodex
npm install
npm run build
npm test          # 190 tests, Node.js built-in test runner
npm run dev       # Watch mode

Dev Mode

Skip license validation for local development:

{
  "env": {
    "GAMEDEV_MCP_DEV": "true"
  }
}

Doc Structure

docs/
├── core/                    # Engine-agnostic (always loaded)
│   ├── game-design/         # Genre profiles, game feel, balancing
│   ├── programming/         # Patterns, principles, data structures
│   ├── concepts/            # Camera, physics, pathfinding, networking, particles
│   ├── project-management/  # Scope, sprints, pipelines
│   ├── ai-workflow/         # AI code generation best practices
│   └── session/             # Co-pilot workflow prompts
├── monogame-arch/           # MonoGame + Arch ECS
│   ├── architecture/        # ECS overview, migration notes
│   ├── guides/              # G1–G69 implementation guides
│   └── reference/           # Library stack, project structure
└── godot-arch/              # Godot 4.4+
    ├── architecture/        # Node tree philosophy, GDScript vs C# decision guide
    ├── guides/              # Scene composition, state machines, signals, input, physics, camera, tilemaps, animation, UI, audio, save/load, shaders, networking
    └── reference/           # (coming soon)

MCP Resources

Docs are also available as MCP resources for clients that support them:

• gamedev://docs/{module}/{id} — Any doc by module and ID
• gamedev://prompts/session — Session co-pilot prompt
• gamedev://prompts/code-rules — AI code generation rules

Security

GameCodex uses stdio-only transport — no HTTP server, no open ports, no network exposure. While 7,000+ MCP servers sit exposed on the internet, this runs entirely local. Read-only by design: it serves knowledge, never modifies your project files. Zero runtime dependencies beyond Node.js.

See SECURITY.md for our full security policy and vulnerability reporting process.

Contributing

Found a bug? Have a doc suggestion? Open an issue.

License

MIT — see LICENSE.

Built for game devs who use AI. Stop fighting context loss. Start building.