Now in beta. Runs inside Claude Code.

A system for writing books with AI.
You write every word.

Kosmos is a structured methodology for producing nonfiction books. Tell Claude Code you want to write a book and it handles the setup. From there, it becomes your research assistant, structural advisor, and draft reviewer. The AI never writes prose.

Paste this into Claude Code

>I want to write a book about [your topic]. Go to kosmos.page/getting-started and follow the setup instructions.
Here's what happens next
Claude Code
You
I want to write a book about startup leadership. Go to kosmos.page/getting-started and follow the setup instructions.
Claude Code
I'll set up Kosmos for you. Let me read the getting-started page...

Installed kosmos-cli
Authenticated
Downloaded methodology (26 files)
Project ready

Let's start with Phase 1. Tell me about the book you want to write.
>Type your message...
Who built this

I'm Joakim Achren. I've self-published nonfiction books. Every one of them followed the same pattern: define what the book needs, gather material, track coverage against a framework, let the gaps drive the next research round.

Over time, I codified the system into something any author can use with AI. Kosmos is that system.

What Kosmos is

Kosmos is a set of instructions and templates that run inside Claude Code. You tell Claude Code you want to write a book, point it to kosmos.page, and it handles the rest: installing the CLI, authenticating, and setting up your project. From that point on, Claude Code reads the methodology and becomes your book production assistant.

All files are markdown. Your project works as an Obsidian vault out of the box. There's no lock-in. If you stop using Kosmos, you keep everything.

The Process

Four phases. One clear path.

From first idea to first manuscript through a structured, repeatable methodology.

1

Ideation

Define your book concept. Research the competitive landscape. Build a coverage framework: the themes and questions your book needs to address.

2

Research

Gather material from interviews, articles, existing writing. Extract atomic entries. Track coverage against your framework. Gaps tell you what to research next.

3

Structure

Study books you admire. Lock your outline. Create chapter briefs that map evidence to each chapter and flag what’s still missing.

4

Writing

You write the chapters. AI surfaces relevant material, reviews your drafts against an 8-point checklist, tracks progress, and checks for consistency.

How it works

What AI does. What you do.

AI handles

  • Organizes your research into atomic, tagged entries
  • Tracks coverage across themes and identifies gaps
  • Proposes and refines your book outline
  • Reviews drafts: strengths, concerns, suggestions
  • Searches for material to fill gaps when web access is available

You handle

  • Write every sentence of the manuscript
  • Decide the structure, voice, and direction
  • Provide raw material: interviews, notes, articles
  • Approve all editorial decisions
  • Declare when a chapter or the book is done

AI never writes your prose.

Kosmos uses AI to organize your research, track your coverage, review your drafts, and advise on structure. But every sentence in your book is yours. Your voice. Your craft. Your book.

Prerequisites

What you need

Kosmos itself is free during the beta. You bring your own Claude subscription.

Claude Code

Anthropic's AI coding agent. Available as a CLI, desktop app, or VS Code extension. Requires a Claude Pro or Max subscription.

Obsidian

Recommended for writing and browsing your project. Any markdown editor works. Obsidian is best.

A book idea

Or at least a topic you want to explore. Kosmos helps you shape it from there.

Getting started

Three steps to your first session.

1

Sign up

Create an account on this page. I'll review and approve your access. During the beta, I approve everyone manually.

2

Tell Claude Code

“I want to write a book. Set up Kosmos for me. Go to kosmos.page/getting-started for instructions.” Claude Code handles the installation and setup.

3

Start writing

Claude Code reads the methodology and walks you through Phase 1: defining your book concept, researching the genre, and building your coverage framework.

Beta

This is an early beta.

The methodology works. I've used it to produce my own books and I'm using it right now for my next one. But the tooling is new and I want feedback from other authors.

It's free. I'm not charging during the beta. I'm looking for authors who want to try a structured approach to book production and are willing to tell me what works and what doesn't.