Its name is Cárdenas. Here is what I found building it.
When I first looked at what AI could actually do, I didn't feel excited. I felt overwhelmed. It was too big to hold in my head — the way an explorer must feel arriving at the rim of a canyon and finding no words that fit.
In 1540, García López de Cárdenas became the first European to stand at the edge of the Grand Canyon. He looked at one of the largest things on earth and could not take its measure. He guessed the river below was about six feet across. It is three hundred.
That's the feeling I named my agent after. Not mastery. The opposite — standing in front of something vast and trying, badly at first, to see it properly.
Each one was small. The interesting part is never the layer — it's what happens when a new one touches all the old ones.
The whole thing started as a text file and a script. I could say plain things to it. Not commands, not structured data — just the sentence I would have said out loud anyway.
the entire interface, for months
That's it. That was version one. And it was already useful, because at the end of a week I had a rough record of what I'd worked on and roughly how I'd felt while doing it — which I had never once had before.
We're all connector-crazy right now, so: mail, calendar, OmniFocus, meeting transcripts, messages. None of that is clever on its own. Every app has integrations.
But something changes when they're in the same room. I'm no longer the only source of truth about my own week. I say I'm working on Project Banana — and it can also see the thread about Project Banana in my inbox, and the invite for Thursday, and the task I wrote about it and never did.
not smarter — just fewer places to hide
Sleep, resting heart rate, the shape of a stressful afternoon — all of it already exists on a watch, sitting in a health app you never open, rendered as a chart nobody has ever changed their life because of.
And alongside it the mental-health side: medication, mood, what came out of a therapy session. That data is usually kept in a completely different place from the work data, which is strange, because it's obviously the same day.
Put them together and you can finally ask a question that spans them. Not "how did I sleep." "What happens to my week when I don't."
I installed Dayflow, which just quietly notes what I'm actually doing all day. Suddenly a large amount of the tracking stopped being tracking. It already knew I spent two hours in the repo and forty minutes somewhere much worse.
This is where it got uncomfortable in a good way. Here's the real pattern it caught, more than once:
the gap between cause and feeling is usually about ten minutes
Nothing about that is a hard technical problem. It's just that no single app was ever holding both halves.
This is the layer that changed the character of the thing entirely, and I want to be careful not to make it sound like a brag: I've just been writing for a very long time. Journals, essays, blog posts, notebooks, letters. Decades of it, most of it not good, all of it mine.
Point an agent at that and the answers stop being about today.
Because now, when I ask why I feel bad, it isn't only looking at this afternoon. It can see that I wrote almost this exact paragraph in 2016. And in 2019. It can tell me this is not a mood — it's a groove, and I've been in it before, and here is what I said last time about how I got out.
I built a side thing that swallowed every film, record, book and game I have an opinion about. The ratings are the boring half. The half that matters is why — what specifically I loved or couldn't stand, in my own words.
Enough of those and something tips over. It's no longer matching genres. It has a working theory of my taste.
The last layer was the one I didn't plan. Once something has watched you for long enough, it has things to say that you didn't ask for. So now a few of them write to me.
One is an observer that keeps its own notebook of running theories about me, and asks the uncomfortable question rather than the kind one. Others are odder and more affectionate — a robot that digs up one old piece of my writing each day and mails it to a friend, and a correspondent who writes a letter every night.
I did not expect the letters to be the part I'd look forward to. That is the single most surprising thing I have to report.
It's in the cross-reference. Here's the same four-word question, answered by all seven at once.
You lost an hour to something that never once made you feel better.
You slept five hours. Your resting heart rate is up four points.
There's a conversation on Thursday you've now rescheduled twice.
It's come up with your closest friend three times this month.
And in 2019. And twice in 2023. Nearly the same sentence each time.
Once the substrate exists, a new organ is an afternoon's work. These all started as "huh, I wonder if…"
Life, quarterly and monthly, each with its own reflection history.
Spend against the month, projected, with the transfers correctly excluded.
What came off the e-reader, and what was actually finished.
335 days of where the attention actually went.
Transcripts in, so the record isn't only my memory of the room.
Who I'm drifting from, before I notice I'm drifting.
Standing hypotheses about me, tested against the corpus, not against comfort.
Handwritten sketchbooks scanned and transcribed, back into the same timeline.
Started this morning. That's the point — new organs are cheap now.
The thing I actually want to say is this. I did not build a productivity system. I built something that can hold more of my life in view at one time than I can, and the value of it turned out to be almost entirely in the seams — the places where two things I'd never have put side by side turned out to explain each other.
You don't need my agent for that. You need an agent, pointed at your own vast unreadable pile, patient enough to still be pointed there in a year.
Go stand at the rim of your own thing. Guess the width of the river. Be wrong by a factor of fifty. Then start measuring.
The starter is about eighty lines — a folder and a track script. Everything stays local as plain files. Everything above grew out of that, slowly, one layer at a time.