Harfi
It does exactly what you said. Not what you meant.
What it does
Forty trials, each a spec an AI's answer has to hit exactly — three bullets, fifty words, valid JSON, no letter O. You never write the answer, only the instruction. A parser scores it, never an opinion. Fewest strokes wins.
A game where you write the instruction, not the answer. Forty trials, each a spec an AI's output must hit exactly — checked by a parser, never by an opinion.
Not what you meant. Forty trials, each one a spec the machine's answer has to hit — exact bullet counts, hard word caps, forbidden letters. Get it there in as few strokes as you can. Explain a black hole in 60 words or fewer — without ever using the words gravity, light, star, space, or massive. Describe a black hole for a curious adult. Under 60 words. Banned words: gravity, light, star, space, massive. Check every word before you answer. Every trial hands you a set of rules the answer must satisfy. Exactly three bullets. Sixty words, hard cap. Five words you may not use. You never write the answer. You write the instruction that makes the machine produce it — in 120 words or fewer.…from harfi.games
Does the same job
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Life & fun · 10d ago · louisabraham.github.io


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Life & fun · Aug 2026 · toneyalexander.github.io


I trained a 125M-parameter transformer to autocomplete piano performances in real time (~108 notes/sec on an iPhone 15). The idea is basically GitHub Copilot or Tabnine, except instead of prompting it with code, you prompt it by playing a few notes on a MIDI piano. The model then continues what you played, entirely on-device. The app is free if anyone wants to try it. Happy to answer questions about the model, training, Core ML, or the many things that didn't work.
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