I built a free AI tell detector after my own Reddit account got 2 'all comments are AI generated' callouts in one day

In 24 hours my Reddit account picked up:

• 3 ModTeam removals
• 2 public callouts of "all comments are AI generated"
• 1 "Calm down with your AI responses. Your credibility goes down hard if you can't formulate sentences on your own"

I was running everything through Claude. Clean writing. The mods spotted it in seconds.

So I sat down and mapped the patterns.

the 12 most reliable AI tells

1. em-dash (—). The single strongest tell. Real people on Reddit use commas and periods. AI loves the em-dash.
2. "delve". Just don't.
3. tapestry / realm / landscape / journey / venture / endeavor. Metaphor cluster nobody actually types.
4. "navigate the X", "unlock the X", "harness the X". Verb-noun combos.
5. "Great question", "Absolutely", "100%", "Exactly this" as standalone openers.
6. "In conclusion", "In summary", "Ultimately,". Essay closers in casual writing.
7. buzzword cluster: leverage, robust, seamless, holistic, streamline, ecosystem. One is fine. Three in a paragraph reads AI.
8. parallel bullet structure. All bullets the same length, all starting with the same verb form. Humans write uneven lists.
9. tricolon rhythm: "X, Y, and Z" lists repeated.
10. uniform sentence length. Humans write some short, some long. AI averages out.
11. Title Case headings in informal comments.
12. "However,", "Moreover,", "Furthermore," sentence openers. Humans use "but" and "also".

I put all of this behind a free in-browser detector. Paste your AI text, see every flag highlighted, fix before posting.

→ https://aitells.vercel.app/

No login, no auth. Drops your email if you want the rewriter when it ships (paste your own writing samples, get rewrites in your voice).

why this might help

If you ship Reddit comments or cold emails written by AI and your conversion is mysteriously bad, this is probably part of it. Detection is more aggressive every month. The fix isn't "stop using AI to write" - the fix is removing the fingerprints.

I'm shipping more rules daily. Open to suggestions if you have a tell I missed.

Source for the detection rules: https://github.com/Perufitlife (will open-source the rule set once it stabilizes).

Also built a Supabase security auditor recently after finding 14 critical leaks in my own CRM: https://perufitlife.github.io/supabase-security-skill/

Same pattern: build the thing you wish existed when you got bitten.