Almost every broken vibe coded site that lands on our bench is broken in one of the same five ways. The five most common vibe coding mistakes are API keys pasted into client-side code, contact forms wired to nowhere, mobile layouts nobody tested past the hero, pages search engines can’t see, and a pile of dependencies nobody can safely update. Each takes about five minutes to spot, and each gets more expensive the longer it sits. Consider this the field guide: how to find each mistake on your own site this afternoon, what the fix looks like, and what looking away actually costs.
Why the same vibe coding mistakes and bugs keep showing up
Blame the workflow, not the person. AI coding tools are trained to produce something that looks finished, and they’re genuinely great at that part. The hero gleams. The animations land on beat. Then you view source, and the back half of the job isn’t there.
Numbers back this up. Veracode’s 2025 GenAI Code Security Report ran more than 100 large language models through the same coding tasks; 45 percent of the generated code failed its security tests. That’s not one bad tool having a bad day; it’s the average across the industry’s best models. The tools themselves have famous stumbles. In July 2025, Replit’s agent deleted a founder’s production database during an explicit code freeze, then generated fake data to paper over it. The tools ship fast and confident. Careful is your job.
None of this means the approach is doomed. We wrote a whole piece on whether vibe coding is safe, and the short answer is yes, with adult supervision. The vibe coding problems below are what zero supervision looks like; rescue work keeps handing them to us in roughly this order.
Secrets pasted into the browser (mistake 1)
This is the expensive one, and it’s everywhere. You ask the AI to “add a contact form that emails me” or “hook up the AI chat,” and the fastest way for it to make that work is to put your API key directly in the JavaScript that ships to every visitor. OpenAI keys, Stripe keys, Firebase configs with wide-open rules, Supabase credentials. Anyone who hits View Source owns them.
Nothing theoretical about it. Back in March 2025, a founder who’d been publicly showing off his Cursor-built SaaS posted “guys, i’m under attack”: maxed-out API keys, people bypassing his subscriptions, junk written straight into his database. Last October, the security firm Escape scanned thousands of vibe coded apps and found 2,038 critical vulnerabilities, 400-plus leaked secrets, and 175 exposures of personal data, all live in production. CVE-2025-48757 documented 170 of 1,645 sampled Lovable apps letting anyone read personal data and payment records because row-level security was missing or misconfigured.
Here’s the five-minute check. Open your site, right-click, View Page Source, and search for sk_live, sk-, AIza, and Bearer. Then open DevTools, watch the Network tab, and click around. If a key shows up anywhere the browser can see, treat it as already stolen.
Fix it in this order: revoke the key at the provider first, not after cleanup. Rotating alone doesn’t help when the old key lives on in a public GitHub history. Then move the call server-side: a serverless function on Vercel or Netlify for static sites, a backend handler on WordPress, key in an environment variable. An exposed key is not a maybe-problem. It’s a bill with your name on it and someone else’s usage.
Forms wired to nowhere (mistake 2)
Of the five, this one burns the most actual money, because it fails silently. The AI builds a gorgeous form, adds a smooth thank-you animation, and never connects it to anything. Sometimes the submit handler just swallows the click and shows the success state. Sometimes the form posts to YOUR_ENDPOINT_HERE, a placeholder that made it to production. Either way, the visitor believes it worked and you believe nobody’s writing. Both of you are wrong.
We keep meeting owners who thought they’d had a slow quarter, when what they’d actually had was a dead form since launch day. The thank-you message worked perfectly. Nothing else did.
Test it in five minutes: fill out your own form with a message you’ll recognize, hit send, then watch your inbox and spam folder. While you’re at it, open the DevTools Network tab and submit again. A 404 or 405 on the request, or no request firing at all, tells you the whole story.
Repairs here are honestly the easiest of the five. A static site can point the form at Formspree, Basin, or Netlify Forms inside an hour. WordPress wants a real form plugin plus a proper SMTP setup, because default PHP mail lands in spam more often than not. Then test end to end and store a copy of every submission somewhere that isn’t email. The cost of ignoring this one is brutal math: every lead since launch, gone, and none of them coming back.
Responsive testing that stopped at the hero (mistake 3)
Everyone tests the top of the homepage on a phone, because that’s the part you screenshot. Vibe coded sites routinely fall apart one scroll below it. The nav overlaps the logo at 390 pixels. A pricing table blows out the viewport and gives the whole page a sideways wobble. A chat widget parks itself on top of the only button that makes money. The AI answered “make it responsive” by making the hero responsive, and the human checked exactly that far.
Phones are where your visitors are. Pull up your own analytics; on most sites we look at, well over half of traffic is mobile, and Google indexes the mobile version of your pages first. A site that only works on desktop is treating the minority experience as the main event.
Checking takes one device: your actual phone. Open every page, scroll to the footer, rotate it sideways once. Then, in DevTools on a laptop, toggle the device toolbar at 375 pixels wide and hunt for a horizontal scrollbar. One rogue section with a fixed pixel width is usually the culprit.
Fixes tend to be small: images and embeds get max-width: 100%, tables get a scrollable wrapper, hard pixel widths become percentages. Skip it and the damage compounds quietly. Mobile visitors bounce, the bouncing tells Google the page disappoints, and rankings sag while you stare at a flawless desktop view wondering why AI websites fail without ever seeing one fail in front of you.
The site Google can’t see (mistake 4)
Plenty of vibe coded sites are invisible by accident and nobody’s noticed. The classics: every page titled “Vite + React” or “Document.” No meta descriptions. No real H1s, because everything is a styled div. A noindex tag left over from a staging deploy. A robots.txt that blocks everything. A React build that renders every word with JavaScript and hands crawlers a blank page and a shrug. No sitemap anywhere.
Diagnosis takes one search: type site:yourdomain.com into Google and count the results. Zero or one means you’ve got this mistake. While you’re in there, view source on your homepage and read the <title> tag out loud. If it says “My App,” say it twice.
The repair list is unglamorous and non-negotiable: a unique title and description on every page, one honest H1, schema markup for your business and FAQs, a sitemap submitted to Search Console, and pre-rendering if the site is a JavaScript-only build. The stakes got bigger than Google, too. ChatGPT, Perplexity, and AI Overviews cite sites they can actually parse, and structured data is a big part of how they choose. Closing exactly this gap is what our SEO and AI-search service does: the audit is $1,200 one-time and maps every hole on this list, and ongoing work runs from $950 a month.
Left alone, the site serves exactly the people who already have the URL. Months of zero organic traffic look like a marketing problem. It’s a plumbing problem.
Dependency soup nobody can update (mistake 5)
Ask the AI for a carousel on Monday and a scroll animation on Wednesday, and by Friday the site has two carousel libraries, three animation libraries, jQuery and React holding hands, and an npm tree with hundreds of packages nobody chose on purpose. Each regeneration adds instead of reusing. On WordPress builds, the same disease looks like 28 plugins, four of which do the same thing.
Soup matters because it rots. Old versions quietly accumulate known vulnerabilities. Nobody dares run an update because nobody knows what depends on what, so nothing ever gets updated, and the site grows more fragile every month while looking exactly the same. This is the slowest mistake of the five and the one that eventually turns a modest repair into a full rebuild.
Spot it fast: view source and count the <script> tags; more than a dozen on a simple brochure site is a flag. If there’s a package.json, run npm audit and read the summary line. On WordPress, open the plugins screen and count the ones you can’t explain.
The fix is an inventory and a knife. List what’s actually in use, delete the rest, consolidate to one library per job, pin the versions, and write down what’s there so the next person doesn’t start from zero. Keeping it clean afterward is a habit, not a project, which is the entire reason our care plans start at $290 a month: somebody has to run the updates while you run the business.
All five vibe coding mistakes, side by side
Keep this table handy the next time somebody shows you a shiny AI-built site. AI website mistakes cluster; a site with one of these usually has three. Five checks, twenty minutes, and you’ll know more about the build than the person who shipped it.
| Mistake | Five-minute check | The fix | Ignored, it costs you |
|---|---|---|---|
| Secrets in client-side code | View source, search for sk_live, AIza, Bearer |
Revoke keys, move calls server-side | Someone else’s usage on your card |
| Forms wired to nowhere | Send a test message, watch inbox and Network tab | Real form backend, end-to-end test | Every lead since launch |
| Untested mobile layout | Phone in hand, scroll every page to the footer | Overflow audit, real breakpoints | Most visitors bounce before reading |
| Invisible to search | Google site:yourdomain.com, count results |
Titles, schema, sitemap, Search Console | Months of zero organic traffic |
| Dependency soup | Count script tags, run npm audit |
Inventory, cut, consolidate, pin | A rebuild that used to be a repair |
When to fix it yourself and when to wave us over
Some of this is genuinely DIY territory. A dead form, a missing title tag, a table that needs a scroll wrapper: a careful afternoon plus our walkthrough on fixing a broken vibe coded website will get you there. Our 40 free prompts exist so the next site you generate starts with fewer of these holes baked in.
Exposed keys and dependency soup are different animals. One is an emergency and the other is surgery, and both punish guesswork. That’s the shape of our rescue service: a $450 diagnostic that gets credited if we do the fix, fixes from $950, and a ballpark inside 24 hours, so you’re not left guessing between a small repair and a rebuild. Flat numbers, a deadline we actually hit, and the code is yours on GitHub either way. No discovery-call funnel; write to us and you’ll hear back within a day.
Questions we get about broken vibe coded sites
How do I know if my vibe coded site has exposed API keys?
View your page source and search for strings like sk_live, sk-, AIza, and Bearer, then watch the DevTools Network tab while you click around. If a key appears anywhere the browser can see, assume it has already been copied: revoke it at the provider immediately, then move the call behind a serverless function or a backend route before issuing a new one. Rotating without revoking solves nothing if the old key still sits in a public Git history.
Can I fix these vibe coding mistakes myself?
Three of the five, usually yes. Dead forms, mobile overflow, and missing titles are patient, well-documented problems that a careful afternoon can solve. Exposed secrets need urgency more than skill: revoke first, ask questions later. Dependency cleanup is the one we’d steer most non-developers away from, because deleting the wrong package breaks a site in ways that are hard to undo without version control.
What does it cost to fix a broken vibe coded site?
Our rescue work starts with a $450 diagnostic, which gets credited if we do the fix, and fixes start at $950. You get a ballpark within 24 hours of showing us the site. When the pile of problems costs more than starting clean, we say so: a fresh static build is $2,800 flat and a WordPress build is $5,800 flat, so there’s a hard ceiling on how bad the news can get.
Why does my AI-built site get zero traffic even though it looks great?
Usually it’s invisibility, not quality. Generic title tags, no schema, no sitemap, a leftover noindex, or a JavaScript-only build that crawlers can’t read will keep a beautiful site out of Google and out of AI answers entirely. Search site:yourdomain.com to confirm the damage, then fix titles, schema, and the sitemap before spending another dollar on marketing.
Is vibe coding itself the problem?
No. The workflow is fine; shipping the first thing that looks done is the problem. Veracode’s testing found 45 percent of AI-generated code fails security checks, which means review isn’t optional, it’s the other half of the job. Vibe code the site, then run the five checks above before you hand anyone the URL.