A watercolor painting of a computer motherboard with a glowing CMOS battery at its center
groundwork·4 min read

AI Needs Two Context Windows

Instructions fade. Guardrails erode. Computers solved this problem in 1984 with 256 bytes and a coin-sized battery.

Share
Copied!

The Brief

This article proposes that language models need a small, protected executive context window alongside the main conversation window to prevent instructions from fading during long sessions. It draws parallels to CMOS memory in computers and prefrontal cortex function in the human brain, citing Stanford research on the 'lost in the middle' problem.


What is the lost in the middle problem in AI?
A 2024 Stanford study found that language models perform best when relevant information sits at the beginning or end of the context window but struggle when it is buried in the middle. During long conversations, early instructions get diluted by later messages and effectively stop being consulted.
What is the two context windows proposal?
The proposal suggests giving language models a small executive window for persistent instructions and guardrails alongside the large main window for conversation. The executive window would always be consulted first and never diluted, similar to how CMOS memory holds foundational settings separate from RAM.
How does CMOS memory relate to AI context windows?
CMOS is a chip in every computer that holds roughly 256 bytes of foundational settings, powered by a coin-sized battery. It remembers critical instructions like boot order and drive location even when the system loses power. The article uses it as an analogy for a small, protected AI instruction space.
How would an executive context window prevent jailbreaking?
Anthropic documented that flooding a model with structured text can override safety training through many-shot jailbreaking. An architecturally separate executive window would not be subject to these attacks because its contents could not be diluted or overridden by conversation-level input.
What role does the prefrontal cortex play in the analogy?
The prefrontal cortex acts as an executive controller in the human brain, maintaining goals and rules while the rest of the brain processes information. When it is damaged, people can still process information but lose the ability to stay on task and hold boundaries, mirroring how AI instructions fade in long sessions.

Last week I was three hours into building an automation when the model started ignoring the output format I'd specified at the beginning. Same session. Same instructions sitting right there in the conversation history. But somewhere around message forty, the format guidance had become wallpaper. Present but no longer consulted.

I scrolled back and found my original instructions exactly where I'd left them. The model hadn't forgotten them in any literal sense. They'd just... faded. Diluted by everything that came after.

A handwritten letter on an old desk, the first lines crisp and dark, dissolving into illegibility toward the bottom What early instructions start to feel like by message forty.

Researchers call this "lost in the middle." A 2024 study from Stanford found that language models perform best when relevant information sits at the beginning or end of their context window, but struggle when it's buried in the middle.1 The instructions that mattered most had become middle.

This got me thinking about an old problem computers solved decades ago.

The Coin-Sized Solution

Inside every computer sits a tiny chip called CMOS, powered by a battery roughly the size of a quarter. It holds maybe 256 bytes of data. Less than a text message. But that small memory does something essential: it remembers the instructions that matter most, even when everything else loses power.2

The CMOS doesn't store your documents or run your programs. It holds foundational settings: how to find the hard drive, what time it is, which device to boot from first. The rest of the system juggles gigabytes. Those 256 bytes stay constant, always present, always consulted first.

How Brains Do It

Human cognition works similarly. The prefrontal cortex acts as an executive controller, maintaining goals and rules while the rest of the brain processes sensory information.3 It doesn't store everything. It maintains what matters. Your intentions. The thing you're trying not to forget while you're distracted by something else.

An airport control tower at night, a silhouetted figure watching over the busy runway below The executive function: small, persistent, always watching.

When the prefrontal cortex is damaged, people can still perceive and process information. What they lose is the ability to stay on task, to remember why they started, to hold boundaries in place while everything else flows by.

Two Windows

What if language models had something similar? Not one vast context window where everything competes for attention, but two: a large workspace for conversation, and a smaller executive window that never fades.

The executive window would hold the persistent instructions and guardrails. It would sit above the conversation, always consulted, never diluted by the growing pile of messages below. The main window could stretch to millions of tokens. The executive window might need only a few hundred. But those few hundred would be inviolable.

Anthropic documented how flooding a model with carefully structured text can override safety training entirely, a technique called "many-shot jailbreaking."4 The instructions that were supposed to matter most get lost in the noise. An executive window wouldn't be subject to these attacks. It would be architecturally separate, like CMOS is separate from RAM.

The Pattern

We've solved this problem before. Computers needed persistent instructions that survived the chaos of runtime. Brains needed executive function that maintained goals through distraction.

A small, protected space where the instructions that matter most can live without being forgotten. We should build it.


References

Footnotes

  1. Liu, N., et al. (2024). "Lost in the Middle: How Language Models Use Long Contexts." Transactions of the Association for Computational Linguistics, 12, 157-173. MIT Press

  2. Wikipedia contributors. (2024). "Nonvolatile BIOS memory." Wikipedia

  3. Friedman, N. & Robbins, T. (2022). "The role of prefrontal cortex in cognitive control and executive function." Neuropsychopharmacology, 47, 72-89. Nature

  4. Anthropic. (2024). "Many-shot jailbreaking." Anthropic Research

Found this useful? Share it with others.

Share
Copied!

Browse the Archive

Explore all articles by date, filter by category, or search for specific topics.

Open Field Journal