Substack is rolling out a new feature that lets readers see how much of a newsletter was written by a human versus an AI. The platform announced an integration with Pangram, an AI writing detection tool, that will analyze posts, comments, and replies on its app. This move could shake up trust in independent publishing, especially if it reveals many newsletters are not entirely human-authored. Main Developments The detection tool scans any content longer than 100 characters, including notes, replies, and comments. Substack will also allow writers to add an optional AI author's note, enabling them to disclose their use of AI. The company told TechCrunch the feature is not about penalizing AI-assisted writing but encouraging transparency through a "how I make this" statement. Publishers can run Pangram on their own drafts before publication. They can also report and remove scans on their own work if they believe the detection was inaccurate. The tool provides an estimate of how much content was written by a human versus AI. Read also: OpenAI Pumps Infrastructure Spending to $750 Billion by 2030 Background Substack CEO Chris Best explained the philosophy behind the feature during an online chat with Pangram founder Max Spero. Best recalled pitching Substack to writers by saying the platform handles everything except the hard part — having an idea worth reading. He emphasized that software should do everything else, but the person should do the hard part. Substack joins a growing list of platforms labeling AI-generated content. Social media sites now label AI-generated photos and videos, while music streaming services have begun labeling and sometimes penalizing AI-generated music. The broader trend reflects increasing concern about AI slop flooding digital platforms. Why It Matters In the short term, this feature could hurt Substack's business by exposing newsletters that rely heavily on AI, potentially eroding trust in its ecosystem of independent news and blogs. It could also damage Substack's reputation as a host of high-quality content. However, over the long term, AI detection could help keep the platform free of low-quality AI-generated material and encourage readers to trust what they read. The feature also gives writers a way to distinguish themselves by being transparent about their process. As Best noted, the core value of a newsletter remains the human idea behind it — something AI cannot replicate. This transparency could become a competitive advantage for writers who do the hard work themselves. What's Next The detection feature will roll out in the Substack app for all eligible content. Writers can begin using the optional AI author's note to disclose their AI usage. The company may need to monitor how readers and writers respond to the transparency, especially if it reveals widespread AI use among popular newsletters.