GrowBlocks Lets Claude Code Build and Ship Games on Its Robinhood Chain Testnet Engine

GrowBlocks, a browser game platform whose Dev Kit runs on Robinhood Chain testnet, has released an MCP server and command-line tool that let Anthropic's Claude Code write a game from a description, test it and upload it. The tool is a public npm package, growblocks, at version 1.1.0.

What shipped

MCP, the Model Context Protocol, is an open standard Anthropic published in 2024 that lets an AI assistant call outside tools. GrowBlocks exposes its Dev Kit that way. A folder created with npx growblocks new already contains the server, according to the company's developer page, so Claude Code or Cursor opened in it can read the GrowBlocks API, play the game in a headless browser, inspect the screenshot, upload a test build and read the platform's review status.

The change is in the loop. An assistant could already write and check a game locally, but a person had to upload the folder, copy the test link and pass any reviewer's note back. Those steps now happen inside the assistant's session. Builds land on an unlisted test link, and GrowBlocks staff review every game before it is listed.

The demonstration

GrowBlocks says one Claude Code session, given a single prompt, built a two-player rooftop racing game called Rooftop Rush in 8 minutes 37 seconds, from prompt to playable test link, with 375 lines of code written by the assistant. Its launch video plays back the session log with the clock on screen, including a step where the assistant flagged four problems in its own screenshot and fixed them before uploading. The test build is public and playable in a browser.

The money, on testnet

Games built this way use GrowBlocks' existing fee split. Of the fees a game's NFTs and coin generate, 70 percent goes to its developer, 10 percent to players and 20 percent to GrowBlocks, paid in test credits with no value, according to the developer page. The company says mainnet rates will be set before mainnet opens.

It also launched blocks, parts of games that one developer publishes and others add to theirs. Of the fees of a live game that ships blocks, 5 percent goes to their authors, paid from GrowBlocks' 20 percent, the catalogue page says, and a block built from another passes 30 percent of its share to the original author. The catalogue listed three blocks at publication, all from GrowBlocks.

The command-line token can manage games and builds but cannot move funds, claim earnings or create collections, which stay in the browser, according to the developer guide.

The Pond Street Ledger and GrowBlocks have the same owner.