Prober.ai

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Inspiration

Many AI writing tools jump straight to editing or rewriting a student's work. While this can make a draft sound better quickly, it can also hide weak reasoning and encourage students to rely on AI instead of developing their own ideas.

We created Prober.ai to make AI a thinking partner rather than a ghostwriter. Our goal is to help students build stronger arguments by confronting the kinds of questions a critical reader would ask.

What it does

Prober.ai is an AI-powered argumentative-writing tutor. Students write their essay in the app, choose a feedback persona, and challenge their draft.

Instead of rewriting the essay, Prober.ai asks focused questions about the student's claim, reasoning, counterarguments, and implications. Students can choose between personas such as Reviewer #2, which gives rigorous academic feedback, and Confused Reader, which identifies unclear ideas.

Before receiving a revision suggestion, students must write a defense or reflection. After that reflection, Prober.ai unlocks a targeted suggestion and a short writing tip. This creates an active learning loop:

[ \text{Draft} \rightarrow \text{Question} \rightarrow \text{Reflection} \rightarrow \text{Revision} ]

The student remains the author throughout the process.

How we built it

We built Prober.ai with a vanilla HTML, CSS, and JavaScript frontend, using Quill as the rich-text editor. The interface has a responsive three-panel layout for selecting a persona, writing an essay, and reviewing feedback.

Our backend uses Node.js and Express. We connect to Gemini through carefully designed prompts that generate persona-based questions. The /challenge endpoint analyzes the essay and returns critical questions, while the /unlock endpoint provides a revision suggestion only after the student has reflected on the feedback.

We also implemented safe Markdown rendering, input validation, request-size limits, keyboard-accessible navigation, reduced-motion support, onboarding guidance, session statistics, and a persistent theme toggle.

Challenges we ran into

The biggest challenge was making sure the AI supported learning without becoming a shortcut. We had to design prompts that would challenge students' thinking rather than simply rewrite their essays.

We also needed to make feedback useful without overwhelming students. To solve this, we limited the feedback to a few focused questions and designed the reflect-then-unlock flow.

Another challenge was making the experience work for different kinds of writers. A rigorous academic reviewer and a confused reader should identify different problems, so we created distinct personas and response formats for each.

Accomplishments that we're proud of

We are proud that Prober.ai changes the role of AI in writing support. Rather than replacing students' thinking, it encourages them to explain, defend, and improve their own ideas.

We are also proud of creating a complete and polished experience in a hackathon setting: a rich-text writing environment, persona-based AI feedback, gated revision suggestions, responsive design, accessibility features, safe AI-output handling, and a clear learning-oriented workflow.

What we learned

We learned that educational AI is not only about generating high-quality content. It is also about designing interactions that promote real learning.

We learned how much prompt design matters when defining the AI's role, and how important it is to balance critical feedback with constructive guidance. We also learned the value of accessibility, responsive design, safe content rendering, and reducing cognitive overload by focusing feedback on one issue at a time.

What's next for Prober.ai

Next, we want to add more feedback personas and support additional writing genres beyond argumentative essays.

We also plan to build progress tracking so students can see how their reasoning improves over time, add educator dashboards for teachers to review student reflections, and conduct user testing with students and instructors to refine the feedback experience.

Ultimately, we want Prober.ai to become a writing companion that helps students become more confident, independent, and thoughtful writers.