Medium launches free AI writing app TK with notes disclosing AI use

Medium launched TK on November 9, giving anyone with a Medium account a free web app that puts an AI assistant inside the writing editor. Alongside help developing and revising drafts, it lets authors publish notes explaining their AI use—addressing the blurred boundary between a writer’s own work and an assistant’s contribution.

The name borrows a publishing convention. Editors use “TK,” meaning “to come,” to mark missing information that needs filling in later. The unusual letter combination makes those gaps easier to spot. Medium’s app turns that placeholder into the name of an assistant designed to help writers fill them.

An assistant inside the draft

Writers summon the assistant by typing “@TK” followed by a request directly in the editor. Medium suggests using it for quick questions that might otherwise send someone to another browser tab, such as checking how many days are in a particular month. That places the request alongside the writing rather than in a separate conversation.

The company also describes a set of more substantial writing tasks, spanning the stage before a draft exists through the point when it needs editorial attention:

• Recover earlier material: TK can bring back pieces of writing previously saved in the app and help users organize what they have written.
• Find a starting point: The app can suggest writing prompts for users developing an idea.
• Revise for publication: Medium says TK will ship with skills for editorial feedback, headline feedback and matching drafts to Medium publications’ style guides.

TK can optionally connect to a writer’s own AI agent through an MCP server—a connection for outside AI tools—or a Claude skill. Medium says this can give the app context about projects, positions and ideas stored in that agent’s memory. The connection is optional, rather than a requirement for using the editor.

Making the writing process inspectable

Medium acknowledges that AI raises the possibility of low-quality content and makes the distinction between human-written and AI-written work less clear. Its response in TK is an author-facing disclosure feature: writers can publish notes describing how AI contributed to their work.

This is a start of what we believe is required to publish in the AI era, which is to make the provenance of writing clear, transparent, and inspectable, right down to the prompting and source material,

Medium, in its launch blog post, quoted by TechCrunch

The app also includes a role for human readers before publication. Medium says writers can share early drafts with other people and receive feedback through a social layer. AI assistance and human responses therefore sit within the same product, rather than making automated suggestions the only source of editorial input.

Web access now, a desktop app later

At launch, TK runs on the web. It supports importing and exporting Markdown, the plain-text formatting format, although Medium says TK is not itself a Markdown app. Those options provide a way to bring existing writing into the editor and take material out again.

There is also a privacy limitation for anyone considering it as a home for unfinished work: writing in TK is not encrypted. Medium describes the app as designed for collaboration and says users will be able to set access permissions. Those permissions control access to work; they do not change the stated lack of encryption.

Medium says a desktop app is on its roadmap. For now, the available release is the browser-based tool, free for Medium account holders; the desktop version remains a planned next step.