Build your own website monitoring with Claude or ChatGPT, or use Relvato? An honest comparison
Build your own website monitoring with Claude or ChatGPT, and you can have a script that loads your checkout in a headless browser by the end of the afternoon. So why pay for a monitoring service? Sometimes you shouldn’t. This is an honest comparison of building your own website monitoring with AI versus using Relvato: what each costs in money and time, what you’ll have to build and keep running, and the cases where doing it yourself is genuinely the better choice.
The short answer
Build it yourself if you have one site, a developer who enjoys this kind of work, simple needs — uptime, a login, a checkout on a site that rarely changes — or requirements no product covers, such as data that must never leave your infrastructure.
Use a service like Relvato if the monitoring needs to keep working without someone babysitting them, if you run WordPress or WooCommerce with plugins that update on their own, if you manage several sites, or if the person who gets the alert isn’t the person who would write the code. The difference is rarely the first version; it’s the next twelve months.
What AI makes easy — and what it doesn’t
AI assistants are genuinely good at the first 20% of a monitoring tool. Ask for “a Playwright script that adds a product to the cart and checks the checkout loads” and you’ll get working code in minutes. Ask for a cron job that emails you when a page returns a 500 and you’ll get that too. For a developer, this removes most of the blank-page effort.
What AI can’t do for you is decide what to do when the script fails at 3 a.m. and you’re not sure the site is actually broken, keep the selectors in sync with a theme update, notice that Cloudflare started challenging your headless browser, or remember to clean up the test orders your checkout script created. The code is the easy part; operating it is the product.
What you actually need to build
A single test script isn’t monitoring. To match what a hosted service does, a DIY setup needs: a scheduler that runs tests on time and retries sensibly; a runner with a real browser (Playwright or Puppeteer) and enough memory for it; scripts for each user flow you care about — login, add to cart, checkout, forms; test accounts and test data that don’t pollute your store; and a way to store results and history.
Then come the parts people forget. Visual regression needs approved baseline screenshots, a diff tool like pixelmatch, masks for carousels and ads, and a way to review and accept intended changes. Re-checking after changes needs a hook into WordPress updates or your deploys. Alerts need email or Slack, deduplication and quiet hours. And something has to watch the watcher, because a monitoring script that silently stopped running looks exactly like a healthy site.
The real cost in money
The cash cost of building your own is low, which is why it looks attractive. An AI subscription while you build — ChatGPT Plus or Claude Pro — is around $20 a month. A small server that can run headless Chrome reliably typically costs somewhere between $5 and $40 a month depending on the provider and how many tests you run; CI minutes (for example GitHub Actions) are an alternative for scheduled runs. Email and Slack alerts usually fit in free tiers, and screenshots for visual tests need storage.
Relvato has a free plan for one site with every monitor it has — you start each run yourself, or schedule it weekly — and paid plans at $29, $79 and $199 a month, where the monitors also re-run themselves on every change and run as often as daily, hourly or every 15 minutes. On money alone, DIY usually wins for a single site. The comparison changes once you count time.
The real cost in time
These are estimates for a developer comfortable with JavaScript and a browser automation library, using an AI assistant throughout. Uptime and SSL tests with email alerts: an afternoon. Reliable login and checkout scripts, with test accounts, a product that stays in stock and cleanup of test orders: one to three days. Visual regression with baselines, masking and a way to approve changes: three to five days. Re-running tests when WordPress updates or code is pushed: two to four days. A simple dashboard with history: another few days. Realistically that’s one to three weeks of part-time work before it’s dependable.
Then maintenance. Selectors break when the theme or page builder changes — the same drift you are trying to catch. Browser and library updates break scripts. Flaky runs need investigating. Expect roughly two to eight hours a month for a small setup, more for a store that changes often. At any realistic hourly rate, a few hours a month costs more than most monitoring subscriptions.
Where DIY monitoring breaks down
False positives are the first problem. A page that loads slowly, a cookie banner that covers the button, a dynamic carousel that changes every visit — each produces a failure that isn’t a real breakage. Without careful handling, alerts get ignored within a week, and an ignored alert is worse than none. Handling this well is most of the work in a monitoring product.
Firewalls are the second. Cloudflare, Imunify360 and security plugins increasingly challenge or block headless browsers, so a DIY test fails with a 403 or a “Please wait while your request is being verified” page that has nothing to do with your site being broken. Third, test side effects: real orders, real emails, real stock changes. Fourth, the bus factor — the monitoring lives in one person’s head and one server nobody else checks.
Where building your own genuinely wins
Control. Your scripts can test anything — an internal tool, a multi-step B2B flow, a check that queries your database, a rule no product would ever offer. Data stays on your infrastructure, which can matter for compliance. There is no per-site pricing, so a hundred low-stakes sites cost the same as one. If you already run end-to-end tests in CI, adding a scheduled run may be a small step.
It’s also worth being honest about Relvato’s limits. It costs a subscription once you outgrow the free plan. Its deepest integration is WordPress and WooCommerce; other stacks get public-page monitors, and re-runs on every push through the GitHub App. It runs in the EU and stores data in the US, so your results leave your infrastructure. And while Business plans include custom monitors, you can’t run arbitrary code the way your own scripts can.
What Relvato does that you would otherwise build
Relvato runs the monitors most sites need in a real browser — checkout, login, payment methods, email delivery — without placing real charges. It keeps approved baselines for visual regression and structure drift, with masks and a review flow so intended changes don’t alert twice.
It re-checks at the moment drift happens: its WordPress plugin reports plugin, theme and core updates, and a GitHub push triggers a re-run on any stack. When a firewall blocks the monitors, it names the layer that did it and shows how to allowlist Relvato. It adds vulnerability and file integrity monitors, and it monitors itself on a public status page.
A sensible middle path
You don’t have to choose one forever. Many teams use Claude or ChatGPT for what they’re great at — a one-off audit, a script for a flow that’s unique to their business, a quick investigation after an incident — and use a monitoring service for the always-on monitors that need baselines, triggers and alerts.
A practical way to decide: put your most important site on Relvato’s free plan for a couple of weeks. If it catches something your own scripts wouldn’t have, or saves you the maintenance hours, it has paid for itself; if your needs are simpler or stranger than what it covers, you’ll know exactly what to build.
Building your own with AI vs Relvato
| Build your own with Claude or ChatGPT | Relvato | |
|---|---|---|
| Cash cost | ~$20/month AI subscription while building, plus $5–40/month hosting and storage | Free for 1 site, every monitor; $29, $79 or $199 per month to have them run on their own |
| Setup time | 1–3 weeks part-time for dependable browser tests, baselines and alerts (estimate) | Minutes: connect the site and choose monitors |
| Maintenance | Roughly 2–8 hours a month: selectors, flaky runs, library updates (estimate) | Handled by Relvato |
| Checkout & login monitoring | You write and maintain the scripts and test data | Built in, without real charges |
| Visual regression & structure drift | Build baselines, diffing, masks and an approval flow | Built in |
| Re-check after updates and deploys | Build WordPress hooks or CI triggers | WordPress plugin and GitHub App (Pro and up) |
| Firewalls and bot protection | Debug 403s and challenge pages yourself | Detects and names the blocking layer, retries |
| Security monitors | Integrate vulnerability feeds and checksums yourself | Integrity, exposure and vulnerability scans, all included |
| Alerts & history | Build email or Slack alerts and storage | In-app on every plan; email, Slack, Teams and Discord from Pro; 7 days to 1 year of history |
| Custom logic | Unlimited — anything you can code | Custom monitors on Business and up |
| Where data lives | Your own infrastructure | EU compute, US database |
| Best for | One simple site, unusual needs, strict data control | Sites that change often, WordPress, several sites, non-developers |
DIY monitoring FAQ
Can ChatGPT or Claude build a website monitoring tool?
They can write most of the code: browser scripts for login and checkout, uptime tests, screenshot comparison and alert emails. What they can’t do is run it for you — scheduling, hosting, handling false positives and firewalls, and fixing scripts when your site changes remain your job.
How much does it cost to build your own website monitoring?
In cash, usually little: about $20 a month for an AI subscription while you build and roughly $5–40 a month for a server or CI minutes. The larger cost is time — typically one to three weeks of part-time work to make it dependable and a few hours a month to maintain it (estimates for a developer using AI throughout).
Is building your own monitoring cheaper than Relvato?
For a single, simple site where a developer’s time is free or already budgeted, often yes. Once you count maintenance hours at a real rate, monitor several sites, or need visual, security and on-change monitoring, a subscription is usually cheaper — and Relvato’s free plan covers one site at no cost.
When should I build my own monitoring instead?
When your data must stay on your infrastructure, when you need tests no product offers, when you already run end-to-end tests in CI, or when you have many low-stakes sites where per-site pricing doesn’t make sense.
Can I use AI scripts and Relvato together?
Yes. A common split is Relvato for always-on monitors — checkout, login, visual and security, re-run after every update — and AI-written scripts for one-off audits or flows unique to your business.