There is a problem with leaving a job you held for twenty one years, and nobody warns you about it. You cannot remember who you worked with.

Not in the sense of having forgotten them. In the sense that the list does not exist anywhere, including in your head. I left Google earlier this month after twenty one and a half years across Search, Maps, ads, mobile, Core, Core ML, and DeepMind, in roles that ranged from running large organizations to writing code with three people. Somewhere in there I met, argued with, mentored, was mentored by, shipped alongside, and occasionally annoyed several thousand people. When I sat down to write my goodbye note, I could produce maybe a hundred and fifty names from memory, and I knew with total certainty that the hundred and fifty were wrong. They were the recent ones and the loud ones. The person I had one extraordinary conversation with in a London conference room in 2008 was nowhere near that list.

This is the sort of problem that used to have exactly one answer, which is that you accept it. There is no roster of everyone who mattered to you, no internal system that will hand you the list. What you actually do is type out the names you can think of, send the note, and add a line asking people to please forward it to anyone you missed. It works, in the sense that something gets sent. It is also a sloppy solution that quietly hands the entire decision to your recency bias. The people you saw last month get a goodbye. The people who changed how you work, fifteen years ago, on a team that no longer exists, do not.

I did not want to accept it. So I did the other thing.

Letting the machine do the remembering

The tool I reached for was Antigravity, paired with the Google Workspace MCP server I had originally built as a Gemini CLI extension. That extension exists because I wanted my terminal to be able to see my calendar. It turns out that giving an agent access to your mail and calendar for ordinary convenience also gives it access to the complete archaeological record of your working life, which is not something I had thought carefully about until I needed it.

The first pass was mail. I had the agent go through twenty one years of sent messages and pull out every address I had ever written to individually. Not mailing lists, not the thirty person threads, not the announcements. One to one mail, or close enough to it, on the theory that if I had bothered to type your name into the To field, we had a relationship worth closing properly. That produced a very large and very stale list, because a lot of those people left Google years ago. So the second pass compared the addresses against an internal directory and kept only the ones still active, which cut it down considerably and also produced a small, unexpected inventory of people I had lost track of.

The second source was calendar. Mail catches the people you write to, but it misses the ones you only ever talked to in a room. So the agent went through twenty one years of my calendar looking for anything that was genuinely a one to one: a recurring weekly, a single mentoring session someone booked in 2017, a skip level, a coffee that got a calendar entry because that is how Google works. Every one of those has a person on the other side of it, and a surprising number of them never once appeared in my sent mail.

Then it merged the two. I had expected this to be the hard part and it was not, for a boring reason: Google email addresses are stable. People change teams constantly and the address follows them, so deduping on the address alone does nearly all of the work. What I was not prepared for was reading the result. Whole eras came back. I would hit a cluster of addresses and remember an entire project I had not thought about in a decade.

The last problem was purely mechanical and almost funny after all that. Gmail will not let you put several thousand addresses on a BCC line. The agent did not raise this, which is worth saying in a post that is otherwise about how capable these things are. I had to notice it and ask. Once I did, it split the list into batches that fit under the limit and drafted the same message across all of them, and I sat there and hit send, over and over, until the list was gone.

What came back

I expected silence. You send a goodbye to someone you shared one project with in 2011 and you expect it to land in an archive folder, if it lands anywhere.

One person wrote back to tell me, politely, that he had no idea who I was. I liked that reply enormously. I assume he was not the only one who felt that way and just the only one honest enough to say it, and I would rather have sent that mail and been forgotten than not sent it at all.

But most of what came back was not that, and the volume of it caught me completely off guard. A solutions engineer in Japan wrote about a Street View collaboration with Nintendo that had been his very first project at Google, and told me I was probably the first real engineer he ever encountered. We were born the same year. He had turned fifty a month earlier and was finding the number about as strange as I am. Someone I managed for only a few months thanked me for trusting him and called it one of the most engaging windows of his career. A former colleague opened by saying he had just been telling someone we both used to work with how much he missed working with me, and then reported that he still has not gotten his motorcycle license because his friends staged an intervention dinner about it. A director in Munich offered a beer if I ever make it back and reminded me of work we did together that I had honestly stopped thinking about. Someone I have known for close to twenty years said he had been meaning to call, and instead of trading contact details we ended up at lunch off campus the following Friday, which is the best possible version of what one of these notes can do.

That is the part I keep turning over. Not one of those replies exists if I send the note from memory.

A hundred and fifty, the number of names I could produce on my own, is roughly Dunbar’s number, the size of a stable social group a human can actually maintain. I do not think that is a coincidence, and I have stopped treating it as a personal failing. My recall of my own career landed almost exactly where the research says it should, which means the ceiling was never effort or affection. It was architecture. Twenty one years builds a network many times larger than the one a head is designed to hold, and the overflow is not forgotten so much as never retrievable in the first place. The agent was not being clever here. It simply was not subject to the constraint.

The people who wrote the most moving things back to me were, almost without exception, the ones my brain had not surfaced. They were on the list because software read my calendar from 2013 and did not care that it was 2013.

The gap this points at

I have spent two years writing about what agents can do, and most of my examples have been about work. Code, pipelines, research, the machinery of building software. This is the first time I have used one for something that was purely about people, and it is the only agentic project I have run where the output made me feel something.

It is also, and I want to be honest about this, a completely unreasonable thing to ask a normal person to do. To get here I needed an agent platform, an MCP server I wrote myself, OAuth credentials, a working mental model of what a tool call is, and enough patience to iterate on the approach a few times when it came back wrong. The capability was extraordinary. The cost of access was absurd.

That gap is the whole reason I am doing what I am doing next. I wrote last week that using agents today is effectively a hobby, and this is the cleanest example I have of why that matters. Everyone leaving a long job has this problem. Almost nobody gets to solve it, because solving it currently requires you to invest in the hobby first. Closing that distance, so that an ordinary person on an ordinary Tuesday can ask for something like this and simply get it, is the work.

Twenty one years of colleagues got a goodbye from me because software remembered what I could not. I would like that to be an unremarkable thing to say.

And to everyone who wrote back: I replied to every thread I could, and I am sure I still missed some. I want all of you to know how deeply your words and your wishes landed. Thank you for that.