Prompt My Game

• 

  Real demo: the assistant changes the character to Bobo, then I play the result. Built with KAPLAY; based on KAPLAYGROUND.

• 

  Ivanna Butterfly Garden: a separately published result at ivanna-butterfly-garden.netlify.app, not a local saved-game sample.

Inspiration

Making a game is easier to understand when there is already something to play. I wanted a creator to start with a working browser game, describe one change to an AI assistant, and play the new version without first setting up a local development environment.

What it does

PromptMyGame is my WebMCP-enabled version of KAPLAYGROUND, an existing open-source browser game editor. The live interface still uses the KAPLAYGROUND name. A creator plays the current game, asks for a change in ordinary language, and keeps the editor open while a compatible assistant works. The AI agent can understand the open project, edit it, run it, and return useful checks. The creator remains the creative director and the play tester.

The editor also works without an AI assistant. People can play, edit code manually, save projects in their browser, and export portable copies.

The open-source foundation

KAPLAY is the open-source two-dimensional JavaScript game engine underneath the project. It provides the building blocks for drawing, movement, collision, input, and sound.

KAPLAYGROUND is the existing web-based editor for creating, editing, playing, and sharing KAPLAY projects. This entry builds on that editor; I did not create its original engine or editor foundation.

KAPLAY grew from Kaboom.js, a JavaScript game engine originally developed by Replit. KAPLAY and KAPLAYGROUND are now maintained by the KAPLAY Team and community contributors. Built-in Crew assets are released under CC0.

What I added for the challenge

During the challenge period I connected KAPLAYGROUND to WebMCP and added the workflow around it. The editor can identify the exact game an assistant is working on, reject an edit made against an older version, apply related file changes together, and separate different kinds of evidence when it runs a game.

What I learned

The hard part was defining what a successful result means when a creator, an AI assistant, an editor, and a running game all share the same project.

Credits

Built with KAPLAY and based on KAPLAYGROUND, by the KAPLAY Team and contributors. KAPLAY grew from Kaboom.js, originally developed by Replit. Built-in Crew assets are CC0. Full license notices remain in the public repository.

Built With

• indexeddb
• kaplay
• kaplayground
• react
• typescript
• vite
• webmcp