Game Builder
An MCP server that helps any coding agent build games. Plug it into Claude Code, Codex, Cursor, Windsurf, Gemini CLI or any other MCP client, then say "make me a game where…". Your agent does the thinking and writing with its own model; Game Builder gives it the game know-how and tools. No API key needed.
It draws on the genres that make up most of the game market and the engines most used for games on GitHub, with open-source games to learn from in each genre.
What your agent gets
| Tool | What it does |
|---|---|
plan_game |
Picks a stack for the idea and returns the playbook plus the matching stack and genre guides, so the agent can pitch before building. |
get_guide |
Any stack or genre on demand: "godot", "unity", "three.js", "roguelike", "tower defense"… |
scaffold_game |
Writes a playable starter (2D web, Three.js first person, A-Frame world, Godot 4) — web starters include a GitHub Pages workflow; returns setup steps for Unity, Unreal, Bevy and other engines, and for multiplayer backends. Never overwrites a folder. |
image_prompt |
Writes a layout-exact prompt for ChatGPT or another image model, so generated sprite sheets line up with the code. |
check_game |
Finds missing asset files, JavaScript syntax errors and PNG sizes. |
playtest_game |
Plays a web game in a headless browser with the keys and clicks the agent chooses, then hands back a screenshot, errors, failed loads and the game state before and after, so the agent can see what it built. |
serve_game |
Serves the game at http://127.0.0.1 so you can play it. |
It also offers the guides as resources (gamebuilder://playbook, gamebuilder://stacks, gamebuilder://genres) and a new_game prompt.
| Stack | Good for |
|---|---|
| 2D web (Phaser, PixiJS, KAPLAY, canvas) | puzzle, casual, idle, card, dress-up, games that run from a link |
| 3D web (Three.js, Babylon.js, PlayCanvas) | first-person exploration, small 3D games in the browser, WebXR |
| Godot | most 2D games and small-to-mid 3D games on desktop, mobile and web |
| Unity | mobile, 3D action, VR/AR |
| Unreal | high-end 3D, shooters, open worlds |
| Bevy, MonoGame/FNA, libGDX, raylib, LÖVE, Defold, Pygame/Pyxel, Flutter Flame | code-first engines and frameworks by language |
| Ren'Py, Monogatari | visual novels and dating sims |
| Colyseus, Nakama, Socket.IO, boardgame.io | online multiplayer |
The genre guide covers 21 genres: action/platformer, roguelike, RPG, shooter, survival/crafting, strategy, tower defense, simulation/management, racing, fighting, sports, puzzle, casual mobile, card/deck builder, visual novel, dress-up, rhythm, idle, horror, party/social deduction and online multiplayer/MMO.
Install
Needs uv (or Python 3.10+ with pipx). The server is on PyPI as game-builder-mcp and runs with:
uvx game-builder-mcp
Add it to your agent:
Claude Code
claude mcp add game-builder -- uvx game-builder-mcp
Codex (~/.codex/config.toml)
[mcp_servers.game-builder]
command = "uvx"
args = ["game-builder-mcp"]
Cursor (.cursor/mcp.json), Windsurf, Claude Desktop and most other clients use the same JSON shape:
{
"mcpServers": {
"game-builder": {
"command": "uvx",
"args": ["game-builder-mcp"]
}
}
}
Gemini CLI (~/.gemini/settings.json): the same mcpServers block.
To run the latest code from GitHub instead of the PyPI release, use uvx --from git+https://github.com/wuisabel-gif/game-builder game-builder-mcp.
Use
Ask your agent, for example:
- "Use game-builder to make a Vampire Survivors-style game for the browser."
- "Make a Godot roguelike with procedurally generated rooms."
- "Build an online party game with room codes where friends join from their phones."
- "Set up a Unity tower defense game for mobile."
- "Write the image prompt for a 4-frame walk cycle, 256 × 256 per frame."
The agent plans, scaffolds, builds, checks and playtests the game itself, then serves it for you to play. The first playtest downloads a headless Chromium (about 150 MB).
Develop
uv run --with . python tests/test_tools.py
Releases: bump __version__ in gamebuilder/__init__.py, merge, then publish a GitHub release tagged v<version>. The Publish workflow builds the package and uploads it to PyPI with trusted publishing.
License
MIT
Metadata
Release files for game-builder-mcp 0.4.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | Provenance | Actions |
|---|---|---|---|---|
| game_builder_mcp-0.4.0.tar.gz | 104.7 kB | With provenance | Details for game_builder_mcp-0.4.0.tar.gz |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Actions Reset |
|---|---|---|---|---|
| game_builder_mcp-0.4.0-py3-none-any.whl | Python 3 | none | any | Details for game_builder_mcp-0.4.0-py3-none-any.whl |
Total release size: 137.5 kB
Release files / game_builder_mcp-0.4.0.tar.gz
| Download URL | game_builder_mcp-0.4.0.tar.gz |
|---|---|
| Size | 104.7 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
d28655b3444a9710d2194471f350d21d2284971a79e0a87a40a51cf2c65c5a98
|
|
BLAKE2b-256 checksum How to use checksums |
9690282a33c9e147171b30b9f709d969e5ef8e41c5d79ff68c1b4c81f48a08d5
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/7.0.0 CPython/3.13.16
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Oct 27, 2026.
Transparency logRelease files / game_builder_mcp-0.4.0-py3-none-any.whl
| Download URL | game_builder_mcp-0.4.0-py3-none-any.whl |
|---|---|
| Size | 32.8 kB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
6ad0e696431f3b54556fdd19d110e01ad834573291b9f2813d95d04802f93aba
|
|
BLAKE2b-256 checksum How to use checksums |
661e93a189473a3c31ab013ce35ff5e8cd0f36ad37101cf15f28fc3a1eba2aa6
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/7.0.0 CPython/3.13.16
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Oct 27, 2026.
Transparency logSecurity for game-builder-mcp 0.4.0
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
Full provenance
All 2 files in this release have been uploaded with provenance metadata.
Attestation for game_builder_mcp-0.4.0.tar.gz
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Oct 27, 2026.
Transparency logA note on package security
PyPI is a repository for distributing packages, not a service for auditing them. While third-party security researchers and our staff do their best to detect and remove malicious packages, PyPI cannot guarantee the quality, security or suitability of any given package.
To learn more about protecting yourself from malicious actors, visit our package security documentation.