GrowBlocks Dev Kit for Claude, Cursor and other AI assistants

Make a browser game with an AI assistant and ship it on GrowBlocks: three.js, Rapier physics, characters, multiplayer rooms and hosting, with no setup.

The assistant reads the API, writes game.js, plays the game headless and looks at a screenshot after every change, reuses parts other developers published (blocks), and pushes an unlisted test build you can share. Nothing goes public until you submit it and GrowBlocks reviews it.

Install

Claude Code (plugin: tools + skill)

/plugin marketplace add Gioluan/growblocks-devkit
/plugin install growblocks@growblocks

Claude Code (just the MCP server)

claude mcp add growblocks -- npx -y growblocks mcp

Claude Desktop: download growblocks.mcpb from the latest release and open it.

Cursor / Windsurf / any MCP client

{ "mcpServers": { "growblocks": { "command": "npx", "args": ["-y", "growblocks", "mcp"] } } }

Terminal: npx growblocks new my-game, then npx growblocks help.

Then ask: "Make me a GrowBlocks game where frogs race across lily pads", or use the make_game prompt.

Tools

Tool	What it does
growblocks_docs	The Dev Kit API (or one section of it)
growblocks_check	Static checks; with play it plays the game headless and returns a screenshot
growblocks_new_game	A new game folder from the starter kit
growblocks_blocks, growblocks_block_info, growblocks_add_block	Find and add published blocks (their authors earn when your game ships them)
growblocks_login, growblocks_whoami	Sign in with a code you confirm in your browser
growblocks_create_game, growblocks_link_game, growblocks_update_game	Make the game on GrowBlocks and set its name, logo and details
growblocks_push	Upload an unlisted test build and get its link
growblocks_status, growblocks_games	Builds, links and the review note
growblocks_submit, growblocks_publish_block	Only when you ask: submit for review, publish a block

Every tool takes dir, the game folder. Prompts: make_game, ship_game. Resources: llms.txt, gb.d.ts.

Money (collections, the coin, earnings) never goes through the assistant: it stays in your browser at growblocks.xyz. Developers keep 70% of the fees their game generates.

Layout

• .claude-plugin/marketplace.json: this repo as a Claude Code plugin marketplace
• plugins/growblocks/: the plugin (.mcp.json runs npx [email protected] mcp, pinned so every install runs the reviewed version, plus the growblocks-game skill)
• desktop/: the Claude Desktop extension; build it with npx @anthropic-ai/mcpb pack desktop growblocks.mcpb
• server.json: the entry for the official MCP Registry
• TERMS.md: the Dev Kit terms

The server is one dependency-free file, growblocks.mjs, published on npm as growblocks.