Build the company brain

The company brain is the single most useful thing in this book. It is also not complicated.

It is a set of plain files and connections that describe your company: who you serve, how you talk, how each process runs, what you decided last quarter and why. Your tools feed it. Your AI systems read from it.

What the brain looks like on disk

Plain text files in folders. Markdown, because people can read it and every AI tool can too. No database, no special software.

brain/
  company.md          who we serve, what we sell, how we talk
  rules.md            what a system may do alone, what goes to a person
  people.md           who owns what, who to ask
  processes/
    invoice-matching.md
    support-first-reply.md
    monday-report.md
  decisions/
    2026-q3-pricing.md
  sources.md          which tools feed the brain and how often

What goes in

• Who you are: clients, offers, prices, tone of voice.
• How work runs: the steps of each process, written by the person who does them.
• Rules and limits: what a system may do alone and what always goes to a person.
• Your sources: Slack, Notion, GitHub, documents and email connected, so the brain does not go stale.

A company.md that works

Keep it to one page. Short sentences. Write it as if you were briefing a smart new hire on their first morning.

# Company

## Who we serve
Operations leads at logistics firms with 50 to 500 staff.
Not a fit: single-person shops, consumer brands.

## What we sell
Two offers. Monthly retainer, and a one-off audit.
Prices live in pricing.md. Never quote from memory.

## How we talk
Plain words. Short sentences. No jargon the client
did not use first. We say "we", not "the company".

## Our three biggest processes
1. Invoice matching (processes/invoice-matching.md)
2. First reply to support (processes/support-first-reply.md)
3. Monday report (processes/monday-report.md)

## A system may never
Send money. Promise a delivery date. Change a price.
Email a client without a person approving it.

## Who to ask
Pricing: Sam. Legal: Ines. Anything else: the ops lead.

A process file that works

This is where the value is. Ask the person who does the task to talk through it while you type. Do not tidy it up. If they say "I check the PO number first, and if it is missing I ping Dana", write exactly that.

# Invoice matching

Owner: Dana (finance ops)
Trigger: a supplier invoice arrives in the finance inbox

## Steps
1. Read the PO number on the invoice.
2. If there is no PO number, stop and ask Dana. Do not guess.
3. Find the PO in the ERP. Compare supplier, amount, currency.
4. Amount within 2 percent of the PO: mark "matched".
5. Anything else: mark "needs review" and say which field differs.

## Good result looks like
One line per invoice: PO number, status, reason if not matched.

## Review
Dana checks the "needs review" lines daily at 10:00.

Setup takes hours

We set up a company brain in hours, and you do not rewrite your wiki first. You start with what exists and connect it. The writing-down happens one process at a time, starting with the three tasks from chapter 2.

If you want to build the first version yourself, our Claude Code Challenge shows how. Day 2 creates a CLAUDE.md file so Claude Code knows your business, stack and preferences every session. Day 5 gives 11 copy-paste prompts for a full second brain with folders, memory, skills and tools.

Keeping it alive

A brain goes stale in a quarter if nobody owns it. Name one owner. Add one rule to your team: when a system gets something wrong, you fix the file, not the question. Every correction then helps every system that reads it.

Scope it per person

A brain that everyone can read everything in will not survive a first security review. Decide early who sees what. Pricing and salary files are not for the support intern. Split the folders by role and give each system access only to the folders its task needs.