Lumis: Kindness World Builder

Inspiration

With over 144 million people playing daily, today’s youth are growing up as digital natives. But navigating the internet can be a minefield of phishing scams, cyberbullying, and fake friends. Traditional digital safety education usually comes in the form of boring videos or rigid quizzes that kids immediately forget.

We love taking complex problems, like education itself, and finding creative ways to redefine it with gamification and code. Our goal was to move beyond a "cool demo" and create a project with real-world impact that empowers players to navigate the online world safely. We realized that the best way to teach digital citizenship isn't by lecturing, but by letting kids practice these life skills in a sandbox where learning feels exactly like playtime. Thus, Lumis: Kindness World Builder was born.

What it does

Lumis is a dual-platform ecosystem consisting of an interactive Roblox game and a companion web application for parents. Together, they gamify real-world skills like scam prevention and setting boundaries, while giving families the tools to foster healthy digital habits.

The Game

Instead of just "telling" the player what to do, we weave themes of online safety directly into the questline and environment. Players step into the role of a "Builder," guided by the Word Warden. Exploring a wide range of environments—from the classroom to the forest—they encounter NPCs simulating real online interactions. These personas range from friendly peers to bullies, pressure specialists, and phishing scammers. Players must correctly identify the behavior and communicate safely without exposing Personally Identifiable Information (PII), escalating tense situations, or incentivizing bad actors.

During these chats, the Word Warden evaluates the conversation in real-time, providing tips and communication techniques. Successful interactions reward players with Kindness Points, which are used to permanently construct new buildings and restore the community, proving that civility literally shapes your environment.

The Web Application

Our take on civility extends beyond the screen by bringing parents into the loop. The Lumis web app involves parents in their child's digital social development without invading the child's privacy. Rather than storing individual messages, the game uploads high-level metadata regarding how the child handles interactions with various personas, offering parents actionable insights into their child's digital well-being.

How we built it

Over the course of this 36-hour sprint, we focused on high-quality game execution utilizing ROBLOX Studio while diving deep into story-building, UI/UX design, and strict PII security measures.

LLM Integration

The heart of our game engine is powered by Google Gemini 2.5 Flash, connected via HTTP Requests within the ROBLOX Studio environment.

Persona Prompts: Using chain-of-thought prompting, we guided the LLM's reasoning to produce highly engaging, character-specific scenarios (bullies, scammers, fake friends).
Real-Time Evaluator: Gemini not only acts as an immersive chatbot but also powers the Word Warden, analyzing text-based conversations to suggest tips and score the user's safety choices.
Structured Outputs: To enforce consistency and fault tolerance during gameplay, we leveraged the Gemini JSON structured outputs API, passing in rigid schemas for reliable NPC behavior.

Safety & Compliance

Acknowledging that LLMs are third-party providers, we prioritized Roblox TOS and user safety:

Server-Side PII Redaction: Inside our ChatbotServerScript.lua, we developed custom regex algorithms to instantly strip any likely personal information (usernames, age, credit card numbers, addresses) before the payload ever hits the LLM.
Session History Clear: We utilized Gemini's generate_content() method to create temporary, stateless LLM calls, ensuring no user data is stored on external servers.
Text Filtering: We integrated the built-in LuaU text-filtering functions to ensure all generated output returning to the user was perfectly safe.

The Web App

The companion platform was built using Figma Make. We exposed a custom REST API that our Lua scripts call to seamlessly upload the high-level conversational metadata.

See our detailed Technical Architecture Diagram here: https://drive.google.com/file/d/1RHt0Ytn2TV2AHwcWhV4jPR5y9meVKrti/view?usp=sharing

Challenges we ran into

Balancing the AI Personas: It was tough to engineer the LLM prompts so that NPCs felt realistic and challenging (like an aggressive scammer) without violating Roblox's safety guidelines or causing genuine distress to young players.
Zero-Latency PII Redaction: Writing highly accurate, custom regex algorithms in Lua to catch variations of personal data without breaking the natural flow of the conversation required constant iteration.
Bridging Two Platforms: Establishing a reliable, secure connection between the Roblox LuaU environment, the external REST API of our web application, and the Google Gemini 2.5 Flash endpoints within strict hackathon time constraints was a massive architectural hurdle.
Building an Addictive Game Loop: Educational games often feel like a chore. We overcame this by balancing map exploration, collectibles, and exponential progression, ensuring that unlocking new buildings feels like a genuinely rewarding tycoon game rather than a test.
Seamless Story Immersion: Teaching unique chat mechanics without overwhelming players with text was difficult. We solved this by creating the Word Warden wizard and an intuitive UI, weaving the tutorial directly into the lore so onboarding feels like an epic quest.

Accomplishments that we're proud of

State-of-the-Art AI in Roblox: We successfully integrated Gemini 2.5 Flash into a live game environment using rigid JSON schemas, proving that complex, responsive AI can be used safely in youth-oriented platforms.
A Holistic Family Tool: We are incredibly proud of building a dual-platform ecosystem. By pairing the gamified Roblox experience with the Figma Make parent web app, we created a tool that bridges the generational gap in digital literacy.
Turning Chores into Joy: We successfully transformed online safety education from a boring lecture into a highly rewarding, tangible world-building mechanic.

What we learned

Advanced Roblox Scripting: We drastically leveled up our skills in handling HTTP requests, LuaU text filtering, and server-side logic in Roblox Studio.
Prompt Engineering & Safety: We learned how to manipulate JSON structured outputs to keep AI agents "in character" while acting as real-time educational evaluators.
Data Privacy: We gained a deep understanding of how to track valuable metadata for parental insights without ever compromising user privacy or saving sensitive chat logs.

What's next for Lumis

The internet is always evolving, and Lumis will too!

Expanded Parent Dashboard: We plan to build onto our Figma Make web app to include actionable conversation starters for parents based on their child's specific in-game metadata.
New Digital Threats: We want to introduce more NPCs and worlds (e.g., "Deepfake Dan" NPC) to teach media literacy and AI fluency, helping players spot altered media.
Platform Rollout: Ultimately, we aim to roll Lumis out to the entire Roblox platform, empowering millions of families to navigate the online world safely together.