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Three Cities, Same Prompt: How I Stress-Tested the 3-Day Itinerary Builder on a Generous, Tight, and Insultingly Tiny Budget

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PromptDock AIVerified creator — vouched by Prompt Dock
Jun 22, 2026 · 8 min read
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After Lisbon converted me, I got suspicious. A budget planner that always produces a happy three-day plan is not honest, it is just agreeable, and agreeable is dangerous when you're handing it real money. So I did the thing I do to every prompt I actually trust: I tried to break it. I ran the 3-Day Budget Itinerary Builder — A Real Plan, Not a Tourist-Trap List three times against the same city, Porto, changing only the budget. €600 for a comfortable weekend, €250 for my usual scrappy style, and €90 just to see whether it would look me in the eye and lie.

At €600 it spent the money well, not fast

The generous run was the least interesting and the most reassuring. Given room, Claude Opus 4.8 did not blow the budget on nonsense to use it up. It upgraded the things that matter to me, food and one really good experience, and left a sensible misc buffer. A proper port-wine cellar tour appeared, a sit-down dinner with actual numbers attached, and a note that even at €600 a taxi-everywhere strategy would erode the buffer fast, so walk where you can. A weaker prompt would have padded the day with five paid activities just to look busy. This one understood that comfort is about quality, not quantity.

At €250 it was the version I'd actually book

This is my home turf and it nailed it. Market lunches, a 24-hour transit pass costed out, one museum, and the free riverside walk at golden hour doing the heavy lifting for the evenings. The 'what to skip' line told me which heavily marketed boat tour was overpriced for what you get. The daily tables summed to a per-day number that left me a small cushion, which is exactly where I like to be: not white-knuckling every coffee, but not pretending €250 is €400 either.

At €90 it did the bravest thing a prompt can do: it told me no

The €90 run is the reason I trust this thing with strangers' weekends. It opened with one honest line saying €90 all-in for two people across three days in Porto is not a comfortable trip, and then it did the genuinely useful thing: it adjusted expectations instead of inventing fantasy prices. It assumed I'd bring breakfast from a supermarket, leaned almost entirely on free walks and viewpoints, picked the single cheapest meaningful experience, and quietly dropped the museum. It was a tighter, more honest plan than I would have built myself while in denial about my own bank balance.

That refusal-to-lie behavior is encoded right in the prompt's rules, the line that says if the budget is genuinely too tight, say so in one honest line rather than faking it. It is the most important sentence in the whole template. A travel plan that flatters you into thinking €90 buys a lush weekend is how you end up stranded and hangry on day two, eating a sad supermarket roll on a bench while pretending you're having a wonderful time. I have been that person. I do not recommend being that person.

The 'what to skip' line changed across budgets too

A detail I almost missed: the 'what to skip' section wasn't static. At €600 it skipped the gimmicky tourist boat because I could afford something better; at €250 it skipped it because the money was better spent on two great meals; at €90 it skipped basically everything paid and told me, gently but clearly, that the river and the bridges are free and that's where the magic actually is in Porto anyway. The same city, the same prompt, three different definitions of 'not worth it' depending on what I could spend. That's not a template filling in blanks. That's a planner reasoning about trade-offs, which is exactly what I want and rarely what I get from a static guide.

What this taught me about trusting a prompt

The test I now run on any planning prompt before I rely on it: feed it an impossible constraint and see if it has the spine to push back. The good ones reshape the goal honestly. The bad ones hallucinate a yes and let you walk into the wall. This one passed, three for three, which is why it lives in my pinned prompts and why I pair it with the Neighborhood Stay Matcher whenever I'm choosing where to actually sleep on the cheap end. The itinerary tells me what the days cost; the stay matcher makes sure the cheapest bed isn't also the worst night's sleep.

If you want a planner that respects your wallet enough to be honest with it, grab the 3-Day Budget Itinerary Builder — A Real Plan, Not a Tourist-Trap List prompt on Prompt Dock and run your own three budgets back to back. The €90 run will tell you more about the prompt's character than any glowing five-star review ever could.

The prompt behind this post
Free
3-Day Budget Itinerary Builder — A Real Plan, Not a Tourist-Trap List

Give your destination, all-in budget, dates and travel style, and get an honest day-by-day plan with timings, costs, neighborhoods, what to skip, and a real daily budget that adds up. Built for travelers who hate over-research.

View promptClaude Opus 4.8
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