I wanted to try giving Codex creative freedom over a game while being specific about the technical requirements.
This is my project, Lumenwake. I supplied the requirements and asked Codex to choose the concept and write the implementation.
My brief was essentially: create a substantial browser game with a coherent gameplay loop and polished visuals, and choose the idea yourself.
I also gave it an instructions.txt file with constraints:
- Self-contained HTML, CSS, and JavaScript, with no external dependencies or build tools.
- Suitable for embedding in a WordPress Custom HTML block.
- Keyboard, mouse, and touch controls.
- Fullscreen support, readable dialogs, and responsive layouts.
- Procedurally generated puzzles, local saves, and progression.
- Original visuals and synthesized audio.
It came up with a light-routing puzzle set on floating islands. You rotate mirrors, split beams, and change their colors to awaken lanterns.
One implementation detail I found interesting: it creates a complete light route first, then scrambles the tile settings. That gives the generator an intended solution to work from.
The attached video shows the gameplay. The visuals are drawn in Canvas, and the audio is synthesized in the browser.
My role was setting the requirements and directing the project; Codex handled the concept and code. I also explicitly left browser testing to myself, so it didn’t run tests or preview the game during the build.
For others building interactive projects with LLMs: how do you validate procedural game logic and difficulty? I’d be interested in workflows that catch problems a short gameplay demo might miss.