I haven't measured it precisely, but my sense is that about 95% of the code I ship these days is written by Antigravity's agent.
I write the other 5%.
I started thinking about what that 5% actually is during Golden Week, when I spent seven solid days working alongside Antigravity. I was trying to sort out what I'd let go of and what I still couldn't — and somewhere in that process, a question surfaced: why do I still reach for the keyboard myself at all?
What I Do While the Agent Works
Antigravity's Agent mode handles tasks end to end. Tell it to "add error handling to this API and write the tests," and it opens the files, edits the code, runs the test suite, fixes failures, and brings the task to completion. I review the result and issue the next instruction.
In my first few months using it this way, I framed it as a productivity story. Faster delivery, shorter implementation cycles. That was true. But after nearly half a year, something deeper has shifted.
What am I doing while the agent runs? The honest answer: I'm thinking.
With my hands off the keyboard, I find myself working through design questions deliberately. Why this structure? Does this data flow actually feel natural? If future-me reads this cold, will the intent be clear? These were always part of coding — but before, I'd run through them half-consciously while typing. Now they're explicit.
The 5% I Can't Let Go
I've been building apps independently since 2014. My catalog — wallpaper, wellness, and mindfulness apps — has accumulated over 50 million downloads. At peak, AdMob revenue was clearing ¥1 million a month. Through all of that, I've come to believe one thing firmly: the gap between apps that connect with users and apps that don't isn't decided by code quality alone.
What makes the difference is how honestly you've answered the question: "Who is this for, and why?"
Antigravity's agent doesn't decide what I build. "Is this feature actually necessary?" "Does this interaction feel natural to the person using it?" "Does the whitespace on this screen communicate stillness?" — those calls are still entirely mine.
The 5% I write myself is made of these accumulated decisions.
Something My Grandfather Taught Me
Both of my grandfathers were temple carpenters — miyadaiku — building shrines and Buddhist temples. Growing up, I heard the phrase "working with your hands is itself a form of devotion" more times than I can count.
I think about that more now, in an era where AI writes code.
My grandfathers used tools too — chisels, planes, saws. The craft wasn't in avoiding tools; it was in developing the judgment to know which tool belonged in which moment. Antigravity is my tool. Developing the discernment to use it well is still work I have to do myself, steadily, over time.
The ratio of what my hands do has changed. My responsibility for what I make hasn't.
Owning the Code I Didn't Write
There's one practice I've stayed consistent about: I read every line the agent writes.
Not just for quality review. Reading the code forces me to understand why a particular implementation was chosen — and to check that against my own intentions. Anything I can't explain, I either ask the agent to clarify or I rewrite myself.
Getting to 50 million downloads as a solo developer took years, and the thread running through it was a sense of accountability for what I shipped. I'd like to keep that, whatever the tools become.
What AI Still Can't Write
One last thought.
The agent can't read intent I haven't expressed. A gut instinct about what an app should feel like, frustration users haven't voiced yet, the particular quality of stillness I'm trying to build into a design — none of that reaches the agent unless I put it into words first.
In 2019, standing outside Kichijoji Station, I looked up and saw a ring of light in the sky above me. Something clicked about visual expression in that moment — a kind of certainty I hadn't had before. When I'm trying to bring that feeling into an app, I want to write each line carefully, one by one.
That's my 5%.
Entrusting 95% to the agent so I can protect the 5% — that's the relationship we seem to have settled into.