Maxime Rivest · 2026-07-06 · notable
Riddle — reMarkable Paper Pro becomes Tom Riddle's diary via vision LLM
Riddle is a Rust app for the reMarkable Paper Pro that captures pen strokes, sends each page as a PNG to a vision LLM, then draws the reply back in flowing script on the e-ink display.
Handwrite on a reMarkable, watch the page ink itself with the LLM's answer — no keyboard, no chat window.
Key specs
| GitHub stars | 536 |
|---|---|
| Hn points | 173 |
What is it?
Riddle is a reMarkable Paper Pro app by Maxime Rivest that turns the e-ink tablet into an interactive diary. You write with the stylus at full 4096-level pressure, and after a short rest the page ships to a vision LLM, whose reply is drawn back onto the same page in cursive.
How does it work?
The Rust app hooks the reMarkable's pen stream and commits each finished page as a PNG. That image is posted to any OpenAI-compatible endpoint (OpenAI, OpenRouter, Groq) or a local `pi` model. The response text streams back through the tablet's e-ink engine so the answer appears letter by letter as if written by hand. Gestures — rest to query, flip marker to erase, five-finger tap to quit — replace on-screen UI.
Why does it matter?
Riddle points at a screen-free, chat-free way to use an LLM: the reader stays inside a paper-book UX while the model reads the whole page's context at once, instead of typed prompts. The MIT-licensed repo also documents two working display backends (windowed AppLoad and a direct e-ink takeover) for other reMarkable hackers.
Who is it for?
reMarkable owners, e-ink tinkerers, agent UX researchers
Try it
Drop the v0.2.0 AppLoad bundle onto a reMarkable Paper Pro and set an API key in `oracle.env`.