There is a specific moment in Harry Potter and the Chamber of Secrets which made generations of readers dream, and which then created the basis for the best memes ever generated. We’re talking about when Harry opens Tom Riddle’s diary and begins to write in ink, then watching the book absorb the writing and respond back to him. That moment no longer belongs only to the imagination of literature, because it came to life thanks to a Canadian developer, Maxime Rivestwhich projected it onto a real device, the reMarkable Paper Prothe electronic ink tablet designed for those who love writing by hand.
In the demo, Claude Fable 5, Anthropic’s most recent and capable AI model, gives voice to the diary. The project, open source and published on GitHub, is called riddle, and through the e-ink tablet you write a sentence on the page with the stylus and, after a short while, the words disappear and are replaced by the system’s response in animated italics.
From the Chamber of Secrets to the ink-absorbing tablet: how it works
Obviously there is no Voldemort horcrux inside the page, even if the appearance of the project could make one think of a sort of MIT-licensed ouija. Instead, there is a language model with visual capabilities, which reads the user’s handwriting directly from the page image and responds in real time. When the user stops typing, the system captures the page as an image and sends it to an endpoint compatible with the OpenAI API format, provided that the chosen template accepts images as input. The answer is written on the page as the AI generates it, without waiting for it to be complete, so the first stroke appears after just a second.
That said, installing it isn’t super easy. For starters, it only works on a reMarkable Paper Pro in developer mode and with a launcher installed. The GitHub page also warns that the tool modifies the device, runs as root, shuts down the manufacturer interface (in takeover mode), and directly controls the e-ink engine. It has only been tested on a reMarkable Paper Pro (ferrari, aarch64, OS 3.26–3.27), so it may not work on other models or OS versions, and those who use it do so entirely at their own risk.
After “riddle” comes the interactive Marauder’s Map
Since Rivest shared his video demo, reactions online have been a mix of amazement, surprise and concern. On Reddit there are those who propose that reMarkable transform it into a flagship function of its next devices. Rivest, for his part, promises that this is only the first chapter, because in addition to riddle he has already shown one Marauder’s Map interactiveanother artifact from the world of Harry Potter.
It must be said that the comparison with the saga holds up to a certain point. In the novel, Arthur Weasley scolded Ginny for trusting the diary: “What have I always told you? Never trust something that can think for itself if you can’t see where its brain is.” Perhaps the most curious detail of Rivest’s project is that for once technology does not chase the magic by trying to explain it, but rather replicates it as it was imagined. Over half a century ago Arthur C. Clarke argued that any sufficiently advanced technology is indistinguishable from magic. Riddle’s diary shows that the opposite is now also true.
