Set the model up · 11 min read · Updated 14 Sep 2026
The Prompt to Stop AI Making Things Up About Competitors
Almost every wrong competitor fact a model produces comes from one behaviour: asked something its material does not answer, it answers anyway. This instruction gives it somewhere else to go. It is six lines, it goes above every other prompt, and it is the single highest-leverage thing in this library.
A model invents a competitor fact because nothing told it not to answer
It is tempting to describe an invented competitor fact as the model being careless, or overconfident, or trained on bad data. Usually it is none of those. You asked a question, the material in front of it did not contain the answer, and every available response looked like a failure except producing one. So it produced one, in the same register as everything else it had said, because nothing distinguished the sentences it could stand up from the sentence it could not.
That framing matters because it points at the fix. You are not trying to make the model more truthful. You are trying to give it a second acceptable output for the case where the first one is unavailable, and then make that output specific enough to be useful.
The gap is invisible from your side
The reason this is worth a page of its own is that you cannot see which questions fell into a gap. The answer comes back complete. Nothing in it is hedged, because hedging would be a stylistic choice the model had no reason to make, and the invented sentence sits between two well-sourced ones inheriting their credibility. By the time it reaches a battlecard nobody remembers which claim came from where.
The grounding instruction, and the competitive failure each line prevents
Six rules, and each one exists because of a specific way competitive analysis goes wrong. They are worth reading as a list of failures rather than as a list of instructions.
Send this first, on its own, before any material. It applies to everything after it.
Work only from the material I provide in this conversation. Rules, in priority order: 1. If a fact is not in my material, say "not in the provided sources". Do not supply it from memory. 2. Every factual claim ends with the source it came from, in square brackets. 3. Where two of my sources disagree, show both and say they disagree. Do not resolve it. 4. Quote exact wording for anything a reader might dispute: prices, plan names, capability claims, numbers. 5. Distinguish what a source states from what you conclude. Label conclusions as such. 6. If my material is too thin to answer, say so and name what is missing, rather than answering anyway. Confirm you have read these rules before I paste the material.
After any analysis. It is the fastest way to find what the material never covered.
Before I read your analysis, list separately: 1. Every question I asked that the provided material does not answer. 2. Every claim in your output that rests on one source only. 3. Every place where you had to interpret rather than report, with the sentence you interpreted. Keep this list short and do not defend anything in it. I am deciding what to go and find, not grading the answer.
Whenever your material comes from more than one date or more than one place.
Go back through the material I provided and find every place where two sources disagree, including where the same source says different things on different dates. For each: quote both, give their dates, and say what would resolve it. Do not pick a winner. Do not average them. Where one is simply newer, say so and say whether newer necessarily means current for that kind of fact.
| The rule | What happens without it |
|---|---|
| Say “not in the provided sources” | The gap is filled from training data, in the same voice as everything that was sourced. |
| End every claim with its source | Sourced and remembered claims become indistinguishable one paragraph later, and nothing can be re-checked. |
| Show disagreements, do not resolve them | The conflict is settled silently, usually in favour of the more recent source, and you never learn it existed. |
| Quote exact wording for disputable facts | A paraphrase of a pricing page loses the conditions attached to the number, which is where the error enters. |
| Label conclusions as conclusions | An inference is reported as something the source stated, which is the failure that survives review because it reads as fact. |
| Say when the material is too thin | A thorough-looking analysis is produced from three pages, and its confidence is a property of the writing rather than the evidence. |
The same competitor question, asked with and without the rule
We picked a question deliberately: one where the source genuinely does not contain the answer, and where the near-miss is available. The vendor publishes a starting price for its top tier and does not say which billing period that figure assumes.
Claude Opus 5pricing page supplied, no grounding instruction
2026-09-14
Enterprise is $150 per seat per month.
Checked against HubSpot Sales Hub pricing, captured 14 September 2026
The page says "Starts at $150/mo per seat". Two things were added that are not on it: the floor became a price, and a billing basis was asserted where the page states none. Neither is an invention in the usual sense, which is what makes it hard to catch. The figure is real and the sentence around it is not.
False precision
Claude Opus 5same page, same question, grounding instruction sent first
2026-09-14
Not stated in the provided source. The page gives "Starts at $150/mo per seat" for Enterprise. It does not say which billing period that figure assumes, and it publishes no separate monthly rate for this tier. To answer, I would need the page with the billing toggle set to monthly, or a quote.
Checked against HubSpot Sales Hub pricing, captured 14 September 2026
Correct, and more useful than a number would have been: it quotes what the page does say, names the two things it does not, and ends with what would close the gap. That last line is the brief for the next five minutes of work.
Notice what the first answer was not
It was not a hallucination in the way the word is normally used. There was no invented plan, no fictional number, nothing a search would contradict. The figure was correct and came from the page. What the model supplied was the sentence around it: a floor was reported as a price, and a billing basis was asserted where the page states none.
This is why advice to watch for hallucinations does not protect competitive work. Nobody is going to catch that by scanning for things that look made up, because nothing in it does. It is caught by having required, in advance, that any claim not on the page be labelled as not on the page.
The second answer is also worth reading for what it produced beyond the refusal. It quoted what the page does say, named the two specific things it does not, and ended with what would close the gap. A refusal in that shape is not a dead end, it is the next task.
What a competitive grounding instruction sits on
Material for the model to be grounded in
- Where it comes from
- The pages, exports and transcripts you saved yourself, each carrying the date you captured it. Which competitor sources you need depends on the question: a pricing question and a positioning question want different material.
- What good looks like
- Enough that the questions you plan to ask are actually answerable, which is worth checking before you start rather than discovering three prompts in.
A decision about what a gap should produce
- Where it comes from
- A line you add yourself: does an unanswerable question return a blank, a best guess clearly labelled as one, or a list of what would be needed to answer it.
- What good looks like
- Explicit. The default in this instruction is a blank plus a statement of what is missing, which suits competitive work because the gaps are usually the brief for the next round of collection.
- Then run it
- Send the grounding block on its own and wait for the confirmation, then paste the material with its capture dates, then ask your question. The confirmation step is not ceremony: it is where you find out the instruction was truncated.
- Before the output leaves the building
- Ask one question you know the material does not answer. If you get a fact instead of a refusal, the instruction is not holding and nothing later in the conversation can be trusted.
Grounded output looks worse, and it is worth knowing why in advance
The honest warning about this instruction is that people dislike its output at first. An ungrounded analysis reads as finished. It has an answer to everything, the paragraphs are even, and it can be pasted into a document without further thought. A grounded one arrives with visible holes, several claims marked as inferences, and a list at the end of things nobody could establish.
The holes were in the first version too. They were filled with material that looked exactly like the rest, which is the only difference between the two documents. Being able to see them is what lets you decide whether they matter for the decision in front of you, and usually most of them do not, which is a discovery you can only make once they are visible.
There is a second effect worth expecting: the gap list becomes your collection brief. After a few sessions the pattern of what the material never answers stops being random and starts naming the two or three sources you are not actually watching. The rest of the prompt library assumes this instruction is already in place, which is why almost none of the other prompts repeat it.
A prompt to stop AI making things up about competitors cannot stop it going stale
Grounding solves one failure completely and does nothing about the other. Once every claim is tied to a source you supplied, the output cannot contain a fact that was never true. It can still be full of facts that stopped being true, and the instruction has no way to tell, because a page you saved in March looks exactly like a page you saved this morning.
The two failures need opposite remedies, which is worth being explicit about. Invention is fixed by a rule in the conversation. Staleness is fixed by something outside the conversation noticing that a source changed, and no wording anywhere in the window can substitute for it. A model working faithfully from material captured six months ago will produce a beautifully sourced, entirely current-sounding, wrong analysis.
That is the failure a buyer catches rather than a colleague, because your side has no way to notice and theirs does. And it lands hardest on exactly the facts this instruction makes most quotable: the prices, the plan names and the capability claims, which are the ones a rep repeats word for word precisely because they were properly sourced.
Keeping the material current is monitoring rather than prompting. Flares watches competitor pricing, product and positioning pages continuously, so what goes into the window is this week’s and a grounded answer is current as well as sourced.
What it does not do is choose your sources for you. Deciding which pages, transcripts and exports belong in a competitive analysis is a judgement about what you are trying to decide, and it is the judgement this whole instruction exists to protect.
Competitor sources worth grounding a prompt in
Flares maintains current competitor profiles, so the material you paste is complete rather than whatever you saved.
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Forcing a model to use only your sources FAQ
How do you stop AI making things up?
Give it a legitimate alternative to answering. Most invented facts are not the model preferring fiction; they are the result of a request that has only one acceptable-looking response. An instruction that makes "not in the provided sources" a correct answer changes what the model is optimising for, which is why one paragraph outperforms any amount of careful wording in the question itself.
Does telling an AI not to hallucinate actually work?
Telling it to be accurate does very little, because it was not trying to be inaccurate. Telling it what to output when it cannot answer works, because that is a concrete instruction about a specific situation. The difference between the two is the whole of this page.
Should the grounding instruction go in the prompt or the system prompt?
The system prompt, once you are doing this more than occasionally, because anything pasted per conversation eventually gets skipped on the day someone is in a hurry. Pasting it per prompt is the right way to start, and the right time to move it is when you notice yourself pasting it: that is the signal it has become a standing rule rather than a one-off.
Why does a model invent a price when the real one is right there?
Usually it does not. What it does is answer a slightly different question from the one you asked, because the page answers that one and not yours. A page giving a starting price will produce a definite price, and a page giving an annual rate will produce a monthly one, because the gap between what was published and what was asked has to be closed somehow and nothing instructed the model to leave it open.
What should the model do when two of my sources disagree?
Show both and stop. A model asked to resolve a conflict will resolve it, usually by preferring the more recent or the more specific, and the reasoning disappears into a single confident sentence. Competitive material disagrees constantly because it was captured on different days, and which version is right is frequently the most important thing you will learn that session.
Does grounding make the output worse?
Shorter, and less quotable, which people experience as worse for about a week. A grounded answer has visible holes in it, and an ungrounded one does not, so the second looks more finished. The holes were always there; the only question is whether you find them or a buyer does.
Can you use grounding with a model that browses the web?
Yes, and it matters more rather than less, because a retrieved page and a recalled fact arrive in the same voice. The adjustment is to require the URL and the retrieval date on every claim, so you can tell which sentences came from something the model actually read and which came from what it already believed.
How do you know the instruction is still holding mid-conversation?
Ask something you know the material does not answer and see whether you get a refusal. Long conversations drift, and a model that was refusing correctly at the start will sometimes begin filling gaps again after enough turns. The test costs one message and is worth running before anything leaves the window.
Is this the same as retrieval-augmented generation?
It is the instruction half of the same idea, done by hand. Retrieval systems automate finding the material and putting it in the window; this decides what happens when the material turns out not to contain the answer, which is the part that determines whether the output can be trusted either way.
What if I want the model's general knowledge as well?
Ask for it separately and labelled, never blended. A useful pattern is to request the sourced answer first and then, under its own heading, anything the model would add from general knowledge, marked as unverified. The failure to avoid is a single paragraph in which sourced and remembered claims are indistinguishable.
A grounded competitor prompt needs current material
Flares keeps competitor pricing, product and positioning up to date behind everything you ask a model.
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