Why won't 'do not hallucinate' stop a model from making things up?

Because the model can't tell when it's guessing. A wrong answer and a right one come out in the same confident voice, so ordering it to be accurate just makes it sound more sure. The fix is to give it an exit, a line like 'if you're not sure, say so explicitly,' so it can flag the gap instead of papering over it.

Why use a prompt for a money plan instead of a budgeting app?

The prompt runs your real numbers two ways, pay debt first or save while paying minimums, and lets your deadline pick the winner. It's only as honest as the spending number you feed it, so pull last month's real total off your bank statement instead of guessing low.

How much of a book should I paste into the book-as-a-game prompt?

About 100 pages at a time, and play them to the end before pasting the next 100. A model can't hold a whole book at once, so feeding it 300 pages makes it invent what the middle said. Convert the book to plain text or markdown first, since PDF is the worst format to hand a model.

Why does the 'test it on a stranger' prompt need a specific persona?

Naming a real person (a hiring manager with 30 resumes, a 55-year-old first-time buyer) is what makes the reaction useful. Write 'a user' and you get a polite shrug. Tell it to be impatient and you find the exact spot where real people give up and leave.

Can a prompt make AI do math reliably?

Not on its own, but you can cut the risk. Tell it to work one step at a time, show every number and where it came from, and say 'I'm not sure' rather than guess. A wrong total looks exactly like a right one, so forcing the work onto the page is the only way to catch it.

Plan your money, gamify a book, test on a stranger

The Take

It’s not so much about prompting anymore, it’s about context. Most people have caught on by now. The people selling prompt packs are pretending they haven’t.

This week’s picks all have ordinary instructions, nothing you couldn’t write yourself. The work is in what each one makes you bring: last month’s spending, the book’s pages, the name of the person you built the thing for.

That’s why the magic-prompt dream won’t die. You can’t go viral with a prompt telling people to dig out a bank statement. People share the prompt that promises the same result with none of the work.

Nobody can sell you context. You already have it.

Seen This Week

1. Make a money plan for a goal you’ll actually hit

You’ve seen the posts. Goodbye financial advisors. Goodbye budgeting apps. Then the prompt underneath spits out 3 lines of money advice generic enough to fit anybody.

This one starts with something you actually want. The vacation you keep saying you’ll take once the money’s there. Put a price on it & a date on the calendar. The prompt handles the step everyone gives up on, the math that says whether your paycheck gets you on that flight in time.

Here's my money each month. Round to the nearest $100, no account numbers.
Take-home: [amount]. Fixed costs: [list]. Everyday spending: [list]. Debt: [balance and rate each]. Saved: [amount].
Goal and deadline: [like "$3,000 for a trip next summer"].
Show me 2 ways to hit it, side by side: pay debt first, or save now while paying minimums. For each, show where my money goes monthly and whether I make the deadline. Find 2 or 3 cuts and aim them at my highest-rate debt. Show your math, and use only my numbers. Tell me which path wins, and if I can't make the deadline, the soonest I can.

Why it works: It runs your real money 2 ways. Pay the debt down first, or save while you pay minimums. The deadline decides which wins, so a trip 6 months out & a trip 2 years out get different plans, not the same “pay off your debt first” everyone repeats.

One gap: The plan is only as honest as the spending number you give it. Most people lowball that. The takeout, the subscriptions you forgot you’re paying for, none of it makes the budget. Fantasy number in, fantasy plan out.

Simple fix: Don’t guess your spending. Pull last month’s real total off your bank statement & paste the ugly number.

2. A prompt that turns any book into a game

The book everyone recommends? You read it, then forget it by the next week. This prompt turns that book into a game you can only win by using its ideas, so they stick because you played them, not because you highlighted them.

One setup step first. The model needs the book as text it can read. A PDF is the worst format you can hand a model, so run it through a free converter & turn it into plain text or markdown.

Paste about 100 pages & play them to the end before you paste the next 100. A model can’t see a whole book at once. Feed it 300 pages & it starts making up what the middle pages said.

You are a sharp, slightly ruthless game master, and the pages I pasted are your rulebook. Drop me into a story where I start with nothing and a goal I can only reach by using the book's ideas. Give the characters their own goals, so they don't just hand me answers. Teach me the book through play, not lectures. When I get something wrong, show me the consequence first, then a hint, and explain only after I keep missing it. An idea only counts as covered once I have used it in the story. Start now, no setup questions.

Why it works: The model has the book’s actual words in front of it, so the game quizzes you on what the book says, not on a half-remembered version of it. “An idea only counts as covered once I have used it” is the line in the prompt that turns reading into remembering.

One gap: The prompt lets the model pick what kind of game you play. It might choose a game you don’t like. A game you don’t feel like playing doesn’t teach you anything.

Simple fix: Name the game in your first line, a detective story, a horror game, an adventure, a turn-based RPG. Pick the one you’d actually play, it’s worth a quick search.

Want to go deeper: Add “make each section one quest, and give me experience points each time I use an idea correctly.” Gamifying it is why it sticks. Watching the numbers go up keeps you playing.

Original post by u/monskull_ on r/PromptEngineering. Link

3. A prompt that tests your work on the person it’s for

You’re too close to your own thing to see what trips up a newcomer, whether it’s a product, a landing page, a resume, or a signup form. This prompt has the model play the person you made it for, seeing it for the first time & saying out loud where it loses them.

You are [the person this is for, like a hiring manager with 30 resumes to read, or a 55-year-old buying this for the first time]. You just landed on what I'll paste below, and you've never seen it before. Walk through it out loud, in your own voice. Tell me what you see, what confuses you, what you don't trust, and the moment you'd give up and leave. Don't give me advice or a fix. Just react as that person would. Here it is: [paste it].

Why it works: Instead of getting advice, you watch someone get confused in real time. That shows you the small problems you stopped noticing months ago. It’s a free focus group.

One gap: The model plays whoever you name. Write “a user” & you get a polite shrug. It also defaults to nice. Real strangers aren’t.

Simple fix: Make the persona impatient. Add “you’re in a hurry and you’ve already tried 3 competitors,” so it tells you what’s wrong instead of being polite.

Via QtheBuilder (AI + Tech, YouTube). Link

The Teardown

Teaching the model to say “I don’t know”

“Do not hallucinate” is right up there with “make me a billion-dollar app. Don’t make any mistakes.” You can type it, but the model can’t obey it.

It can’t tell when it’s making something up. The incorrect answer & the correct one come out in the same confident voice.

So what do you write instead? A thread on r/PromptEngineering asked exactly that, & the top comment is worth stealing:

If you are uncertain or lack sufficient information to answer
accurately, say so explicitly. Do not infer, speculate, or fill
gaps with plausible-sounding information. Cite your reasoning and
flag any claims that may be incomplete or unverified.

Prompt Teardown

One line is doing most of the work here. “Say so explicitly.”

Picture where a model usually goes wrong. You ask about something it half knows. Halfway through the answer it runs out of real knowledge.

The one move left is to keep writing & hope you won’t notice. Every sentence comes out in the same steady voice, so you don’t.

“Say so explicitly” gives it a way out. It can stop & tell you.

A liar who sounds confident is harder to catch than one who says “I might be wrong.” The model’s “I’m not sure” is the only warning you’ll ever get that something’s invented.

Now look at the lines people paste at the end of their prompts. “Rate your confidence 0 to 100.” “Make sure every answer is 100% accurate.” “Do you understand?” Every one of them orders the model to sound confident, & that silences the only warning you had.

Build Up

Keep the good part, the first line. Then there’s everything else models make up, the facts, the sources, the numbers.

Math matters here because this issue’s first pick runs on it. Both paths in the money plan lean on compound interest, the debt growing against you, the savings growing for you. A model predicts what an answer should look like instead of calculating it, & a wrong total looks exactly like a right one. Add this to any prompt that asks for math:

1. Do the math one step at a time, month by month.
2. Show every number you use and where it came from.
3. Show the result of each step before moving to the next.
4. If you are not sure about any number, say "I'm not sure"
   and ask me. Do not guess.

Now every step is on the page where you can check it. That’s why the money plan up top says “show your math.” Math is the example, not the rule. Reword the 4 steps & the same trick works on facts, sources, dates, quotes.

You’re not stopping the model from guessing. The win is getting it to raise its hand before it does.

Top comment by u/Appropriate-Owl-2696 on r/PromptEngineering. Link

Plan your money, gamify a book, test on a stranger

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