Detecting AI-written text on social media - Moving beyond the em-dash
AI on social media like Reddit and LinkedIn have detectable patterns.
Humans are amazing pattern matchers. We’re great at detecting when something is just…off.
That’s how I feel about almost all Reddit posts nowadays. It feels like 80% of reddit posts and comments I read are just AIs talking to each other.
It’s not just the —, it’s the sense it’s not a real person.
Honestly? AI has a strangeness to how it writes that creates smells. You can detect it with some basic tricks.
Curious if you’ve seen the tells, too?
The tells
Many human-written posts contain these naturally. However, the tell comes from the fact that most human posts do not contain many of these at the same time, consistently across posts / content.
Words
AI loves to use specific words.
Substrate - I’ve gone my whole life hearing absolutely nobody use this word, and now it’s everywhere.
Curious - Nobody is that curious to use this word so often.
Resonates - Not everything in life is deep and meaningful unless you’re a robot
Phrases
They also like using these phrases a lot:
“It hits hard…”
“Here’s what actually happened”
“Rare to see <X>”
“The wild part”
“You weren’t imagining”
“Nobody warns you…” / “Nobodys talking about”
“What kills me…”
“The funniest part”
“We need to talk about”
“The real issue is”
Structure
AI has some specific structures it gravitates towards.
Staccato sentences.
“This is <X>. That is <Y>.”
“Not <X>. Not <Y>. <Z>.”
“Just <X>, <Y>”
Lists - particularly if they start with bold.
Removal of the subject from a sentence.
“Left the station yesterday.” vs. “I left the station yesterday”
Comparators and Metaphors
“not <X>, but <Y>”
“<A> was <X>. <Z> is <Y>.”
Odd pause insertion in written content
“Sometimes I just…. <X>”
Sometimes - all lower-case - some people have prompted to try and sound more human
Examples in triples or quads.
Varied but predictable sentence lengths “<Sentence>. <Short fragment> <Shorter fragment>”
eg. “I talked to all of my team that day. Some were mad. Most curious.”
Intents
LLM-written content often does what I call overframing - prepping the user before the primary content that isn’t contextually necessary for the situation.
Trust-building framing
“Honestly…”
“Genuinely asking….”
Buttering-up
“That’s rare.”
“The <X> is real…”
“Exactly this”
“Good point”
Positioning as authority
“Sharing what actually matters…”
Circumventing objections
“You’re right to push back…”
“You’re not wrong…”
Offering engagement
“Happy to <X>”
Oddities
Weird, out of place metaphors and comparisons. AI likes to insert examples that people wouldn’t draw comparisons towards naturally
“The dog looked at me like I was a fish”
Categories
I’ve noticed a few categories of written content that have tell combinations:
Engagement-bait
These posts seem to want to generate engagement - some tells:
Attempts connection
“Curious if anyone else…”
“Am I the only one…”
Requests honesty
“Just looking for genuine takes”
Ends with an engagement prompt
“Curious if…”
“If I may ask….”
“How are you…”
Fake engagement
These posts just seem to be generating engagement:
Give kudos
“Glad you’re doing <X>”
Often ends with a statement or question:
“Do you notice <X>”
Ads
Many of these posts are just trying to sell something. Some are up-front and have appropriate disclaimers. Others are stealthy - they do it by casually name-dropping it in the post alongside other better recognized names.
For example, you’d see a post on “AI Workflows” that mentions popular tools like n8n, Claude, etc. and then see a random product casually name-dropped in the middle as a core part of the workflow like “potato-ai for cleaning up”.
It positions the product as a peer or equal in relevance to the other listed items.
News sharing / Info sharing
Someone shares knowledge or news to present themselves as an expert, sometimes accompanied with an ad.
Factoid along with a personal impact.
“<X> just figured out <Y>. You’re <Z>.”
Description about why it is mind-blowing.
Unnecessary levels of detail to establish credibility.
Opinion.
Examples
Many of these posts exhibit the tells from above. While it doesn’t prove it was AI-generated or edited, enough of them creates a ‘smell’ where I don’t even bother reading it anymore.
These aren’t all the tells. As AI and prompts evolve, it will rapidly change. But once you see it, you can’t unsee it, and you start to realize that a lot of the internet might just be bots talking to bots.
Gefroh is product and technology executive in Kirkland, Washington that writes about leadership, management, operations, and AI.