I used this:

#!/usr/bin/python3 import subprocess import time import random with open("/tmp/x") as f: t = f.read() for c in t: subprocess.call([ "xdotool", "type", c ]) time.sleep(abs(random.gauss(0,0.07)))

And pasted a random Hacker News comment:

Authenticity Score 81 Highly Authentic

Words per minute: 162 Keystroke variance: 52ms Paste attempts: 0 Window/tab switches: 4 Pauses (≥10s): 0 DOM manipulations: 0

You failed.

- Screencap and OCR the prompt

- feed it to an llm to answer

- use a tool [1] to emulate human typing cadence.

- Use a tool to send mouse events to the browser window.

[1] https://multilogin.com/blog/paste-as-human-typing/

not sure if you have any feedback at the end but if you do the alternative is feedback poisoning in your training set to mark AI stuff as real and real stuff as fake. The former is automatable and if there were a good reason you could probably mechanical-Turk a large number of people at low cost to do it for real and give feedback that they were actually AIs.

The following by "Claude Slopson" (Claude Opus asked to write an answer that was obviously AI) scored 87% authentic:

> Ah, what a fantastic question

> For me, it's Breaking Bad–and honestly? It's not just a show, it's a masterclass in storytelling that fundamentally reshaped the television landscape.

> What keeps drawing me back? The way it seamlessly blends moral complexity with edge-of-your-seat tension is nothing short of breathtaking. Walter White's transformation isn't just compelling–it's a profound meditation on identity, ambition, and the human condition itself.

> But here's the thing–it's also deeply rewatchable. Every frame is meticulously crafted. Every detail matters. The foreshadowing alone is chef's kiss!

> Whether you're a first-time viewer or a seasoned fan, Breaking Bad offers something for everyone. It's a testament to what happens when visionary creators push the boundaries of their medium.

> In an era of endless content, some shows simply transcend. This is one of them.

> 10/10, would recommend! What's YOUR comfort rewatch? Drop it below!

(HN strips the emojis, but don't worry–they were there)

A paper on this was just submitted.

"We demonstrate that this class of defenses is insecure against two practical attack classes: the copy-type attack, in which a human transcribes LLM-generated text producing authentic motor signals, and timing-forgery attacks, in which automated agents sample inter-keystroke intervals from empirical human distributions."

https://arxiv.org/abs/2601.17280v1

There are tons of USB dongles available for about $10 containing a programmable microcontroller. You connect to the dongle from another device over wifi and it can act like a keyboard typing out whatever text you want using a model of human typing, perhaps even your own.

>Pasting and DOM manipulation are disabled to ensure all writing is original.

>We track telemetry such as typing speed, pauses, tab changes, and window focus events.

People figure out ways around this for like...Runescape bots and other low-stake situations. I don't think it would hold up to anything other than casual users. Seems like an agent could whip something up in Auto-HotKey or something.

I get this is the extreme end, but if this gets popular enough, can't you write like a custom 'keyboard' driver that just takes AI input and 'types' it? Random delay between keystrokes, whatever....

It also can't be used to verify existing work, right? I can't see if a student's essay is LLM-written. Is there any real-world use you see? Or is this just a fun toy?

> Open chatgpt in second tab > Type what chatgpt says yourself

The only "AI proof" writing tool is those blue books you take exams on in college.

I pulled up a 2nd browser next to your site. I typed the prompt into Gemini, and manually typed what Gemini said and removed em dashes as I typed. It said it was 100% genuine.