A 180-person company runs on 47 things. Nobody in the building could name more than twenty.

Ferncastle keeps office plants alive in twelve cities. Before it could hand any work to AI, it had to write down what it already ran on. This is that list, square by square, with the six nobody owns left in and the one that had quietly stopped marked.

things the company pays for or depends on

run on their own, by a machine

run by a person, by hand, every time

stopped eighteen days ago, and nobody noticed

Each square is one thing Ferncastle runs on: an account, a tool, a spreadsheet, or a workflow that runs by itself. Rows are the eight functions of the business. Hover or tap a square to read what it is, who owns it, what it costs, and when it last ran. Ferncastle is a worked example; its inventory is invented to show the instrument.

The problem I had

I could not hand work to an AI that I could not name. When I started running my own business on AI, the first thing I built was not an agent. It was a list of everything the business already ran on, with what each thing cost and who touched it. My own note from the day I decided the order of these pages: "gather all of the information to find the tech stack."

Show them that they need an inventory. Show them that they need to lock in their plans. Understand where all their context is. Map that out completely.

Ferncastle's version is the one every executive lives. Forty approved tools, a subscription for each, and the watering schedule still on a whiteboard in the greenhouse. Ask the leadership team what the company runs on and you get twenty answers and a shrug.

What the picture shows

Forty-seven things. Nineteen run on their own: the billing run, the sensor alerts, the route planner, the renewal reminders. Twenty-two are run by a person, by hand, every single time, which is the honest name for most of what a company calls "our systems." Six have no owner anyone can name, and two of those are still being paid for.

One square matters more than the rest. The watering-schedule alerts, the workflow that tells a technician a building's plants are drying out, stopped eighteen days ago. Nobody noticed, because nothing was watching it. The plants noticed.

The thing you have no inventory of is the thing that breaks silently.

What changed

The inventory is the first document, because every other document refers to it. The plan names the tools it depends on. The rhythm says which ones run unattended. The rules say what an AI may touch. None of that can be written until the list exists.

Once it exists, it answers two questions every Monday at six in the morning, without a person: what are we paying for, and is it still running. A workflow reads every vendor, every account, and every workflow, and marks the ones that went quiet. The whiteboard becomes a row with an owner and a date.

You cannot hand work to a machine until you can name the work.

Receipts

Where this came from

Example: Ferncastle is a worked example. It is a fictional 180-person company, and its 47 things, their costs and their owners are invented to show the instrument. No client's data appears on this page.
Real: The instrument itself runs on my own business: five tables holding 23 accounts and services, 399 workflows and functions, and 72 skills, refreshed every Monday at 6am Central by a workflow that has fired three weeks running as of 8 September 2026.
Method: One row per thing the business runs on. Kind, function, what it is for, who owns it, what it costs a month, whether a machine or a person runs it, and when it last ran. Two questions every Monday: what are we paying for, and is it still running.
Unfinished: On my own inventory, the fifteen-minute vendor check has not fired since 15 August, and the row that watches it says so every morning. The lesson on this page came from that row.

A 180-person company runs on 47 things. Nobody in the building could name more than twenty.

The inventory template, and the Monday routine that keeps it true.