What an AI Second Brain Actually Is
You will connect your everyday tools to an AI assistant (level 1) and understand how to grow it into an index.md that links your emails, calls and documents on your own computer (level 2).
Was Sie brauchen
An AI app such as Claude, ChatGPT or Gemini (I set up level 1 in Claude)
Access to the tools your work lives in: email, call notes, CRM, documents
For level 2: an AI that can read your files and write a text file (I mention Claude or Codex)
Schritt für Schritt
Spot what your AI is missing
Notice that Claude, ChatGPT or Gemini knows the internet but nothing about your business or personal life. List where your knowledge actually lives: your calls, your emails, your CRM and your documents. That list is what your second brain needs to reach.
Connect your daily tools to the AI (level 1)
Take the tools you use every day and connect them to the AI. With that access, the answers to your questions come from your own data, so they are more precise. This is level 1 of an AI second brain.
Know where level 1 stops
Expect level 1 to get you about 50 to 60 percent of the way. Things you do often never get logged: an email to a prospect that never reaches the CRM, or what you said on a call. That information ends up scattered everywhere.
Ask the AI to read everything into an index.md (level 2)
Instead of only connecting tools, ask the AI to read everything inside them: your emails, your CRM, your business documents or topics you enjoy. Have it write the connections it finds into an index.md file. The .md part just means a plain text file.
Let the AI link related items
Check that the index links things that belong together. Example from the video: an email to person A and a call transcript with person A. The AI reads both, notices the connection and shows it in the index.
Decide what goes into your index
Choose the sections your index lists, for example all your clients, processes, offers and decisions. You decide what goes in, so the second brain is shaped around how you already work. You do not need to change your habits to build it.
Keep the index updated
Each time you add a new email, have the AI read it and add it to the index. Updating it every time keeps everything in sight of the AI, and you can then reach it from a single app such as Claude or Codex.
Start today with level 1 in Claude
Open your Claude account and connect it to the accounts and tools you use daily. In my experience this is largely enough to start. Move to level 2 when you get more advanced: the brain then sits on your own computer, so you can switch AI apps whenever you want.
Claudehttps://claude.ai
Bonus: build a second brain from your books
If you have books saved on your computer, ask the AI to build a second brain from them so you can see how they match and link with each other. Useful for brainstorming or research.
Worauf Sie achten sollten
Stopping at level 1 and assuming the AI sees everything: anything you never logged (emails to prospects, what was said on calls) stays invisible.
Being put off by the .md file: it is only a plain text file.
Changing how you work to fit a system: decide what goes in so the second brain fits the way you already work.
Letting the index go stale: it only helps if new emails and documents get read and added each time.
