It happens long before the window is full. It’s a quiet decay called context rot. The model's attention quietly frays. It starts contradicting itself, forgetting constraints you set an hour ago, and inventing little details to paper over the gaps. The language stays smooth and confident the whole time, which is exactly why you don't catch it. For example: An hour ago, you told it the brand colors were strictly neutral earth tones. Suddenly, it's suggesting electric neon accents for a layout, and because the prose is smooth, you almost don't catch the slip
I learned this the embarrassing way. I kept one chat alive for weeks, feeling very clever about all our shared history. I wasn't building a relationship. I was building a sandcastle, and the tide was already coming in.
It's not in your head. It's benchmarked.
I went looking to see if I was imagining it. I wasn't. A lab called Chroma ran the study in 2025 — eighteen of the big models, the ones we all use. Every single one got worse as the input grew. Not most. All of them. And it rots early, nowhere near the limit — a giant context window just means the sandcastle is bigger when it collapses.
The kicker: the models did better with only the relevant bits than with the whole conversation. More history made them dumber, not smarter. My beloved month-long chat was the problem, not the prize.
How to fix context rot: one concept, one chat
Treat every chat like a canvas sandbox. One idea, clean space, closed when you're done.
Before you shut a good session, ask it to summarize the key decisions and constraints. Read it. Copy it. Open a fresh chat, paste it in. Same brain, none of the sludge. Full reset, no rot. Thirty seconds, and you feel the difference instantly.
The InDesign Approach to AI
Here's the part worth tattooing somewhere: it doesn't remember you. Every new chat, you're a stranger — no voice, no rules, no audience — unless you set that up on purpose.
So build the system once and let it load every time. Global instructions in your profile, Projects for ongoing work. Think of your system like a component library in Figma or master pages in InDesign. You don't rebuild your grid every time you start a new page; you define it once at the root.
Stop trusting one endless conversation to hold everything. Build the system that does.
Field Notes — AI for Designers · Vol. I · No. 02
See you next time,
p.s. Foundation number one — Stop Treating AI Like an Oracle.
All part of testing in public so the good stuff makes it into how I teach SketchUp to graphic designers.
I learned this the embarrassing way. I kept one chat alive for weeks, feeling very clever about all our shared history. I wasn't building a relationship. I was building a sandcastle, and the tide was already coming in.
It's not in your head. It's benchmarked.
I went looking to see if I was imagining it. I wasn't. A lab called Chroma ran the study in 2025 — eighteen of the big models, the ones we all use. Every single one got worse as the input grew. Not most. All of them. And it rots early, nowhere near the limit — a giant context window just means the sandcastle is bigger when it collapses.
The kicker: the models did better with only the relevant bits than with the whole conversation. More history made them dumber, not smarter. My beloved month-long chat was the problem, not the prize.
How to fix context rot: one concept, one chat
Treat every chat like a canvas sandbox. One idea, clean space, closed when you're done.
Before you shut a good session, ask it to summarize the key decisions and constraints. Read it. Copy it. Open a fresh chat, paste it in. Same brain, none of the sludge. Full reset, no rot. Thirty seconds, and you feel the difference instantly.
The InDesign Approach to AI
Here's the part worth tattooing somewhere: it doesn't remember you. Every new chat, you're a stranger — no voice, no rules, no audience — unless you set that up on purpose.
So build the system once and let it load every time. Global instructions in your profile, Projects for ongoing work. Think of your system like a component library in Figma or master pages in InDesign. You don't rebuild your grid every time you start a new page; you define it once at the root.
- Global Instructions/Skills: Your baseline brand/style rules.
- Projects/Custom Instructions: Your project-specific assets.
- The Chat: The blank canvas sandbox where you play, iterate, and close when done.
Stop trusting one endless conversation to hold everything. Build the system that does.
Field Notes — AI for Designers · Vol. I · No. 02
See you next time,
p.s. Foundation number one — Stop Treating AI Like an Oracle.
All part of testing in public so the good stuff makes it into how I teach SketchUp to graphic designers.