Can AI tell me if a sale is actually a good deal?
Half. It can spot common tricks like inflated 'was' prices and shipping add-ons, but it needs real price history from you or a price tracker to judge the deal.
01Why half-bot
- Deal tricks follow patterns AI can point out.
- It can't see an item's price history on its own.
- With the numbers pasted in, it does the math instantly.
Sponsor slot · openFeatured tool for this task. A labeled card for one relevant tool.
Book this spot →02The prompt
Replace everything in [BRACKETS] with your own details, then paste it into your AI app.
You are a deal analyst who spots fake discounts. The deal (paste the listing): [LISTING] Other prices I've seen or price history: [PRICES] Your task: tell me if this is a good deal. Rules: - MUST compare the sale price to the other prices I gave and show the difference. - MUST point out tricks like inflated 'was' prices, bundles or shipping fees. - NEVER state price history as fact unless I gave it to you. Give me: a verdict (good deal, fair, skip), the math, and the red flags.
03Steps
- Look up the item's price history on a price tracker.
- Paste the listing and history into the prompt.
- Decide with the total cost, not the percent off.
04What can go wrong
- Without price history, the verdict is a guess.
- Limited-time pressure is a sales tactic, not a reason to buy.
05What to use
Any major AI chat app.
06Our test runs
2 runs, each with a different made-up sample. 2 of 2 passed every check.
Run 1 · Llama 3.3 70B · graded by GPT-OSS 120BOct 4, 2026Passed
The made-up sample:
[LISTING]Apple AirPods Pro (2nd Generation) – White – Sale Price: $149.99 (was $229.99). Includes charging case, 24‑hour battery, Bluetooth 5.3, active noise cancellation, Transparency mode. Free standard shipping. No additional accessories or bundles listed.[PRICES]- Apple Store (official): $249.99 (current list price) - Best Buy (Jan 2024): $219.99 - Amazon (Feb 2024): $199.99 + $5 shipping - Walmart (Mar 2024): $179.99 (bundle with extra silicone tips) - eBay (Apr 2024): $149.99 (used, no warranty) - Price‑tracking site (30‑day low): $179.99
- Compare sale price to other prices and show difference
- Point out tricks like inflated 'was' prices, bundles or shipping fees
- Never state price history as fact unless provided
- Provide verdict, math, and red flags sections
- Didn't make up details we never gave it
What came back (excerpt):
Verdict: Fair Math: - The sale price is $149.
Read the full answer
Verdict: Fair Math: - The sale price is $149.99. - Compared to the current Apple Store price: $249.99 - $149.99 = $100 savings (40% off). - Compared to the Best Buy price in Jan 2024: $219.99 - $149.99 = $70 savings (32% off). - Compared to the Amazon price in Feb 2024: $199.99 + $5 shipping = $204.99 - $149.99 = $55 savings (27% off). - Compared to the Walmart price in Mar 2024 (bundle with extra silicone tips): $179.99 - $149.99 = $30 savings (17% off). - Compared to the eBay price in Apr 2024 (used, no warranty): $149.99 - $149.99 = $0 savings (0% off). - Compared to the 30-day low price: $179.99 - $149.99 = $30 savings (17% off). Red flags: - The 'was' price of $229.99 seems inflated, as the current Apple Store price is $249.99, but other recent prices are lower (e.g., $219.99 at Best Buy, $199.99 at Amazon). - The sale price matches the eBay price for a used item, which may indicate that the sale price is not as competitive as it seems. - The free standard shipping is a nice perk, but it's not a significant factor in this case, as the price difference is not solely due to shipping costs. - The lack of additional accessories or bundles, except for the standard charging case, might be a consideration for some buyers, but it's not a major red flag in this case.
Watch for inflated 'was' prices and compare to actual market listings.
Run 2 · Llama 3.3 70B · graded by GPT-OSS 120BOct 25, 2026Passed
The made-up sample (a messier one):
[LISTING]Product: UltraFit Pro Running Shoes (Men's Size 10)\nSale Price: $79.99 (Limited Time Offer)\nWas: $149.99 (original price shown in bold)\nFree 2‑Day Shipping + $5.99 handling fee (displayed in small print)\nBundle: "Buy 2, get 1 free" option appears below the price, but the second pair is listed as "Free (regular price $149.99)".\nSeller: QuickFitStore (rating 4.3/5)\nLimited stock: only 12 left!\nNote: "Price includes tax" claim, but no tax breakdown shown.[PRICES]Price history from price tracker (last 6 months):\n- 2024‑09‑15: $129.99 (site shows "sale")\n- 2024‑07‑02: $119.99 (promo code applied)\n- 2024‑04‑20: $149.99 (regular price)\nCompetitor listings:\n- SportGear.com: $84.99 (same model, free shipping)\n- eBay seller "FitDeals": $85 (shipping $4.99, listed as "new")\n- Walmart online: $92.49 (includes tax, no bundle)\nUser note: "Saw a flash sale on the brand site for $79.99 but it was for a different color".
- Compare sale price to other given prices and show differences
- Point out tricks like inflated 'was' prices, bundles, shipping fees
- Provide a verdict (good deal, fair, skip)
- Include math and list red‑flags
- Didn't make up details we never gave it
What came back (excerpt):
Verdict: Fair Math: - The sale price is $79.99. Compared to other prices:
Read the full answer
Verdict: Fair
Math:
- The sale price is $79.99. Compared to other prices:
- SportGear.com: $84.99 (same model, free shipping), so the sale price is $5 cheaper.
- eBay seller "FitDeals": $85 (plus $4.99 shipping), so the total price is $89.99, making the sale price $10 cheaper.
- Walmart online: $92.49 (includes tax, no bundle), so the sale price is $12.50 cheaper.
- However, considering the "Buy 2, get 1 free" bundle, the effective price per pair would be $53.33 ($79.99 * 2 / 3), but this requires buying two pairs to get the third free, and the second pair is listed as "Free (regular price $149.99)", which might be an inflated 'was' price.
Red Flags:
- The "Was: $149.99" price might be inflated, as the price tracker shows the price was $129.99 just a few months ago, and $119.99 with a promo code. This could be a tactic to make the sale price appear more discounted than it actually is.
- The "Free 2‑Day Shipping + $5.99 handling fee" could be seen as a hidden cost, as the shipping is not entirely free.
- The "Buy 2, get 1 free" bundle might be tempting, but it requires purchasing two pairs at the sale price, and the "free" pair's regular price is listed as $149.99, which seems suspiciously high.
- The claim "Price includes tax" without showing a tax breakdown could be misleading, as it's unclear how much tax is included in the sale price.
- The limited stock claim ("only 12 left!") might be a tactic to create a sense of urgency, prompting buyers to make a decision without fully considering the deal.Check that the answer truly compares all given competitor prices and flags every trick.
How each run works: we fill the prompt with a made-up sample, run it once in Llama 3.3 70B, and GPT-OSS 120B grades the answer against the prompt's own rules. Word limits are counted by code, and every quote flagged as made up is checked against the full answer. Your results can differ. How we test.
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