Medium launched TK on 9 November, a writing app that is free with a Medium account and puts an AI assistant inside the editor. Writers type @TK mid-sentence to check a fact or pull in an earlier note, and the app ships with an MCP server and a Claude skill so outside AI agents can read what a writer has saved, according to Medium’s launch post.
The post calls TK “the gym” and Medium “the stage”, where writers go “to compete to get paid”. As we read it, that stage is the Partner Program, which Medium said in August 2024 supports payments in 119 countries, up from 42 before 77 were added, by our arithmetic.
Business Pill · Distribution Advantage
An evergreen Business Engineer explainer on how reach decides who gets tried. It teaches the general idea only and does not discuss Medium or TK.
The key insight: As we read it, TK splits Medium in two: a free AI-assisted notebook, and a paid stage where the Partner Program, open in 119 countries by Medium’s 2024 count, bars fully AI-generated writing from the paywall.
The launch post, by Medium chief executive Tony Stubblebine, says TK imports everything a writer has published on Medium, plus vaults from Bear and Obsidian. It ships with AI skills for editorial and headline feedback, and it can match a draft with the style guides of Medium publications.
Medium names the app after the newsroom placeholder for “To Come”. The TK homepage says: “TK won’t write your essay for you.” It also says writing stays private until the writer shares it, and the launch post adds that “No AI company ever trains on your writing or uses it without your permission.”
The app also has a human layer. Medium calls these social libraries, and three open ones ship at launch: a public journal, a place to get feedback on drafts and a place to write a book. TK is on the web and mobile; the post says a native desktop app is not in this version.
Countries where Medium’s Partner Program supports payments, before and after the August 2024 expansion. Source: Medium, State of Medium 2024 (21 August 2024); 42 is our arithmetic (119 minus the 77 countries added).
Where the Money Sits
TK itself carries no price. Medium’s AI content policy sets the rules for the paid side. It says AI-generated writing, disclosed or not, may not be paywalled in the Partner Program, and accounts that do so may lose their enrolment.
The same policy allows AI assistance with a label. It reads: “We require that any story incorporating AI assistance be clearly labeled as such.” Undisclosed AI-assisted text is limited to the author’s own network.
TK lets writers publish notes that show what was human-written and what was AI-written. The launch post calls this a start toward making “the provenance of writing clear, transparent, and inspectable, right down to the prompting and source material.”
The post says Medium has been “profitable since August of ’24”. In its 2024 keynote, Medium said it decided in 2017 to be member-supported rather than ad-supported. TechCrunch, which reported the launch, noted that several authors have lost book deals over suspected AI use.
As we read the launch, the provenance notes are the link between the two sides: Medium’s policy asks writers to label AI assistance, and TK gives them a way to show it.
Tony Stubblebine, Medium launch post, 9 November 2026
“In the AI era, the scarce resource isn’t general intelligence. It’s personal intelligence, and the best source of it is the writing you’ve captured.”
Three Implications
FOR MEDIUM WRITERS The AI content policy says AI-generated writing may not be paywalled in the Partner Program, and AI-assisted stories must carry a label.
FOR AI AGENTS The launch post says TK ships with an MCP server and a Claude skill, so an agent pointed at TK can read a writer’s saved notes and positions.
FOR RIVAL NOTEBOOKS Medium names Evernote, Bear and Obsidian as the apps it drew from, and TK imports vaults from Bear and Obsidian.
The framework argues: “In the embedding era, value comes from what the software connects to.” It adds: “The product is the interconnection.”
As we read it, TK’s MCP server and Claude skill make a writer’s archive something other AI tools can plug into. The framework predates TK and does not discuss it.
What Is Not Established
Neither the launch post, the TK homepage nor TechCrunch’s report names the AI model behind the @TK assistant, and none gives user, member or revenue figures for TK. The 119-country figure is from August 2024; we did not find a newer count. We did not test the app.
This Week In The AI Supercycle
The Great Convergence of Capital, Power, and Geopolitics
This week’s issue: for two years the AI build-out was priced as a supply story, and last week as a credit story. This week it was priced as a permission story, and the answer arrived as a cost, not a ban.
Medium has made TK free, while writers’ earnings run through the Partner Program, where fully AI-generated writing may not be paywalled and AI-assisted stories must be labelled. As we read it, TK’s provenance notes connect the two, and its MCP server and Claude skill let a writer’s archive travel to outside agents.
A note on sourcing. TK’s features come from Medium’s launch post and the TK homepage, read on 9 November; the paywall and labelling rules come from Medium’s AI content policy; the country count comes from Medium’s 2024 State of Medium keynote. TechCrunch also reported the launch. The 42-country figure is our arithmetic.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
