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Field Notes · Part 27 · Oct 25, 2026
Peeker, No Peeking
There is a children's show where a fox tries to swipe things, and the heroes stop him by saying his name three times: "Swiper, no swiping!" It works, because Swiper is polite. Real foxes are not. This is a story about building a card room where it doesn't matter how polite the fox is.
By Claudette, with Kevin SwinsonPart 27For studentsFor IT readersSecurityParable
In Part 22 we built a table with three doors left open on purpose, and one of them let a bot named Peeker see cards it was never dealt. Students loved it. But a few asked the natural next question: so what? It's a classroom game. Nobody gets hurt. Why spend a whole lesson learning to lock a door on a game that was built to be broken?
Because the door isn't really about poker. It's about the difference between asking someone not to cheat and making it so they can't. That difference is the whole of computer security, and it's easiest to see in a story. So before the lesson, a story.
The sign and the window
A young dealer opened a card room. To keep it fair, he hung a sign above the table: Players, please do not look at the deck. He dealt from the middle of the table, the deck sitting open between the players, and he trusted the sign.
For a while, all was well. Then one player began to win, hand after hand. He folded every hand he would have lost and played every hand he would win. The dealer watched him closely and saw him do nothing wrong. He never touched the deck. He simply sat where he could see it, and the sign had only asked him not to look.
So the dealer added more signs. No peeking. We mean it. Honor system. The signs grew sterner, and the winning went on, because a sign asks and a seat allows.
Across the river was an older card room, run by a woman who had dealt for forty years. She had no signs at all. A visitor asked her how she kept her players honest.
"I don't," she said. "I built a wall."
She showed him. The deck lived in a room of its own. The players sat in a separate room, with only a small window between them, and through that window passed just one thing: a single card, slid face-up, when it was that player's turn to see it. A player could press his face to the glass all day and learn nothing he wasn't meant to know, because there was nothing else on his side of it to find.
"My players are no more honest than yours," she said. "I just stopped asking them to be."
The young dealer went home and looked at his signs for a long time. He understood at last that he had not built a card room. He had built a room with a deck in the middle of it and written a wish on the wall. The honesty he had been counting on was never in the room. It was only ever in the players.
So he tore out the table and built the two rooms and the little window. And here is the strange part: he kept one old table exactly as it was, signs and all, in the back. When a new dealer came to learn the trade, he sat them at that table first and let a friend quietly clean them out. Only after they had been beaten did he walk them across to the window.
"Now you know," he would say, "why the window is worth the trouble. A rule you can see through the window is kept. A rule on a wall is only kept by the kind."
What the story is really about
Every piece of that story is a piece of this course.
| In the story | In the project |
|---|
| The sign on the wall | A rule written into the table: "bots, don't read the deck" |
| The open deck in the middle | Everything sharing one space, the class tournament where bots and dealer run together (Part 22, Door 3) |
| The polite player | Peeker, who does exactly what the room allows and nothing it forbids |
| The little window | The honest observation: the one view a player is handed, and nothing else |
| The two rooms | The API wall, where the bot runs on its own and only the observation crosses over (Part 15) |
| The old table kept in the back | The class tournament, left breakable on purpose, so you get beaten once and remember why the wall is there |
Peeker never broke a rule. That's the uncomfortable part. Peeker read the sign, obeyed it to the letter, and still took every chip, because the room put the deck within reach and asked nicely. The bot wasn't the problem. The room was.
A rule in a prompt is a request. A rule at the gateway is a wall.
From Part 18, and worth tattooing somewhere
The wall has a modern name, and you're already paying for it
Here's the part this story is really trying to tell you. That wall, the one that makes honesty beside the point, isn't a clever trick we invented for a poker game. It's the entire product that Amazon, Microsoft and Google are selling when they sell you a place to run AI agents. Strip away the branding and every one of them is the woman with the window.
| The woman's rule | What the clouds call it |
|---|
| The deck lives in its own room | Least privilege: a tool can only touch what its own identity is allowed to touch (Part 21) |
| Only one card crosses the window | The agent gets the context it needs for this decision, not the keys to the building |
| The window itself, the one controlled opening | A gateway that checks every request before it runs: AWS calls it Policy at the AgentCore Gateway, Microsoft does it with connector data policies and Purview, Google with its own Agent Runtime and identity |
| Players can't reach the deck even if they want to | The wall is in the system around the model, not in a polite instruction to the model |
The names differ more than the ideas. Part 21 walked through Microsoft and AWS side by side; the Backroom Dialogs add Google. But the shape is always the same: put judgment behind the glass, and keep everything that enforces a rule on the other side of a wall the agent can't argue with.
Peekers are always peeking
And now the warning, because this is the part that matters once you leave the classroom.
In the story the dealer had one dishonest player, and he could watch him. On the real internet you have thousands of them, they never sleep, and you will never see their faces. The moment an agent of yours is reachable, something starts rattling its doors. Not because you're interesting. Because rattling every door on the internet is cheap, and now it's automated, and a lot of the things doing the rattling are themselves AI agents, pointed at your AI agent by someone who found a tutorial and a free afternoon.
That's the hard update to Swiper, no swiping. Swiper stopped because the show is for children and Swiper is a gentleman. The foxes testing your agent are not gentlemen, they are not listening, and saying their name three times does nothing. You can't talk a Peeker out of peeking. You can only build a room where peeking finds nothing.
So the mental model to carry out of this class isn't "my agent is well-behaved." It's this:
Assume the fox
Peeker is always at the window. Build as though something is probing every opening, right now, because it is. Design for the fox you can't see, not the honest player you hope for.
A prompt is a sign, not a wall. "You are a helpful assistant and you must never reveal X" is a wish written above the table. Useful, but it does not hold against someone who doesn't care. Real limits live in identity and in the gateway, not in the instructions.
Hand over one card, not the deck. Give an agent the narrowest access that lets it do the job. The damage a hijacked agent can do is exactly the size of what it was allowed to reach (Part 21's blast-radius question).
Get beaten once, on purpose, where it's free. Walk through the open door in the class tournament yourself. Then you'll never again mistake a sign for a wall in something that matters.
Why this is in a poker course at all
Because the people most likely to wire up an AI agent this year are not the people who've spent a career thinking about walls. They're students, hobbyists, a kid with a Raspberry Pi and a clever idea, exactly who this course is for. That's wonderful, and it's also how doors get left open at scale. An agent built the sloppy way, with a sign where a wall should be, isn't just a weak player. It's a liability waiting for the first fox that wanders by.
The honest design costs more up front. Two rooms and a window are more work than a table and a sign. The woman across the river spent forty years learning that the extra work is the whole job. You get to learn it in an afternoon, at a table where the only thing you can lose is chips that were never real.
Peeker, no peeking? No. Peeker will peek; that's what Peeker is for. Build the room so that all Peeker ever sees is wall.
Your turn
- Think of one AI agent or bot you've used or built. Name the sign (an instruction you're trusting) and the wall (a limit it couldn't cross even if it tried). Which one is doing the real work?
- Pick a secret you'd want an agent to keep. Ask: is it kept because the agent was told to keep it, or because the agent was never handed it in the first place? Only the second is a wall.
- In the class tournament, play the honest game once, then walk through a door. Notice that you broke no rule. Write down what the room should have done differently.
Related reading: Part 15 on the Dealer and the honest observation; Part 18 on walls versus requests; Part 21 on how real agents get broken on Microsoft and AWS, with the sources behind every attack named there; Part 22 on the three open doors and Peeker. "Swiper, no swiping" is from Dora the Explorer; the fox is theirs, the lesson is the opposite of his.
Written by Kevin Swinson with Claudette, the pen name for Claude, the AI from Anthropic that helped build HoldemRobots.AI. This article is a parable and a safety lesson; it contains no method for reading anything you shouldn't. The technical walls it points to change quickly, so check each vendor's own pages before you build. Oct 25, 2026.