Try this: pull up your longest prompt and count how many rules sit buried in the middle, not the first two, not the last one. A Redditor named u/Ok_Negotiation_2587 ran that exact test in r/PromptEngineering and found the same pattern every time. Write ten requirements into a prompt and check the output line by line. The first two survive. The last one survives. Everything sandwiched in the middle quietly vanishes, and the model never admits it dropped anything.
Quick start: plant one throwaway rule in the middle of a real prompt, run it five or six times, and count how often it survives. Then bookend your actual constraints, make the model restate the job before answering, and split the message when nothing else works. Here’s the full breakdown.
The Redditor’s test is almost embarrassingly simple, and that’s what makes it useful. Bury one trivial rule in the middle of a long prompt, something like “end your answer with the word done.” Run it a handful of times. Count how often it actually shows up. That number tells you how much of your prompt’s middle is actually being read.
Step 1: Run the plant test 🧪
Take a prompt you already use for real work. Somewhere in the middle, not the opening line, not the closing one, add a throwaway instruction. The original poster’s example is “end your answer with the word done.”
Run it five or six times back to back. Tally how many responses actually end with “done.” That number is your real hit rate for anything you bury mid-prompt, not the hit rate you assumed you had.
Step 2: Bookend the rules that actually matter
Once you’ve seen the leak, stop trusting the middle to hold anything critical. State your non-negotiables in the first lines of the prompt. Put context and background in the middle, where losing a little detail won’t wreck the output. Then close with the same rules again as a short checklist, exactly like this:
Before you answer, these must all be true: 1. under 200 words 2. no bullet points 3. no mention of [competitor] 4. ends with a question.
The middle is where explanation lives. The start and the end are where commitments live. Mixing them up is exactly how a “no bullet points” rule turns into a bulleted list.
Step 3: Make the model show its homework
The stronger move from the post is asking the model to restate the job before it does the job:
Before answering, list every requirement in my message as a numbered list, including ones that are only implied. Then write the answer. Then check the answer against your list and mark each requirement as met or not met, and fix any that are not.
This catches trouble before you’ve read a single word of the actual answer. If your prompt has ten requirements and the restated list only shows eight, you already know which two were never going to survive.
Step 4: Split the message when it keeps failing
If a prompt carries more than a handful of hard rules and the restate trick still isn’t enough, split it. Send the task first. Send the style rules as a second message reacting to the draft. Two short messages beat one long one that gets skimmed top to bottom.
What your results actually mean
If “done” survived every single run, your prompts are cleaner and shorter than most people’s. If it survived about half the time, your middle is a coin flip, and you’ve likely been losing constraints for weeks without noticing. If it barely survived at all, you have a real problem. Tone rules, formatting rules, and “don’t mention the competitor” all live in the same buried middle. All of it gets quietly ignored, the same way your test rule did.
The author’s explanation lines up with what’s already documented about models and long text. Models give more weight to the start and the end, and less to the middle. Your constraints aren’t being refused. They’re being underweighted, and nothing in the output admits it.
Extra tips 📋
- Count the restated list against your actual prompt instead of skimming it. The restate step can miss the exact same rule the final answer misses, so treat it as a check, not a guarantee.
- Repeating constraints costs you length, so only bookend the rules that actually break something when dropped. Don’t repeat every minor preference just because you can.
- Save your restate-and-check paragraph somewhere you can paste fast. The original poster keeps theirs as a two-keystroke snippet in a browser extension called AI Toolbox, one they work on themselves. A plain saved note works just as well.
One commenter on the thread, u/jpetter75, brought up Kahneman’s research on memory. People judge past experiences by the most intense moment and the ending, and the beginning just sets the baseline. Prompts seem to run on the exact same wiring, minus any sympathy for whatever got lost in the middle.
Nobody in the thread had hard numbers on exactly how many hard rules a single prompt can hold before they start dropping. That’s still an open question. But the plant test costs you thirty seconds and tells you more about your own prompts than guessing ever will.
Run the “done” test on the next prompt you send before it matters. Then go bookend the two or three rules you actually can’t afford to lose, and watch your outputs stop quietly ignoring you 🏴☠️
Frequently Asked Questions
Q: Do I need to worry about this “middle problem” in all my prompts?
Only if you’re writing longer prompts packed with constraints (5+). Short prompts with just a few rules don’t trigger this effect, so you’re fine. The issue really only shows up when there’s enough material to weight unevenly.
Q: Can I use bold or caps to protect middle constraints instead of restructuring?
It helps, but it’s not reliable enough to be your main strategy. Commenters mentioned that “intense direction” (emphasis/formatting) does improve things, but the real safeguard is moving your critical stuff to the start and end of the prompt.
Q: Is this just how AI models work, or is it a bigger pattern?
It’s bigger than just AI. One commenter brought up Daniel Kahneman’s research on human memory, we tend to weight the peak moment and the ending way more than the middle. So this might be how minds just naturally work, whether they’re human or machine.
Q: How solid is the “restate and check” trick?
Pretty solid, but not bulletproof. The restate step can miss the same constraint that your answer misses, so it’s not perfect. That said, combined with splitting long prompts into two messages, it’s your best bet for catching problems before they happen.
The middle of a long prompt is where your constraints go to die
by u/Ok_Negotiation_2587 in PromptEngineering