Drift monitoring is a Pro feature (and part of every Team workspace). Add the URLs that matter to Monitor, and Metaspry re-checks them every day and alerts you when a page’s score drops below your threshold or a required tag starts failing - so you find out before your audience does.

The pain

You ship a redesign on Tuesday. The new template silently changes og:image. You find out from a Slack share that looks broken on Friday afternoon.

The industry calls this template drift - one CSS or partial change cascades across many pages and nobody notices until rankings move or shares stop converting. Drift monitoring brings that check down to single-URL granularity.

What each check compares

Every day Metaspry scans each monitored URL with the same 19 audit rules and compares the result with the previous check:

Score - the weighted 0-100 number and its band: 80 and up is healthy, 50-79 needs work, under 50 is failing. A failing required rule caps the band at needs work, whatever the score.
Rule results - which rules got worse or recovered since the previous check (for example og:image now failing, or the description now too long).

The daily check does not re-run the AI-readiness (AEO) checks and does not compare tag values one by one. For tag-level changes, open the scan: its Changed since card and Compare show which tags changed against earlier versions of the page (see Compare scans).

How it works

Add a URL on the Monitor page, or click Monitor on a scan (that reuses the scan’s score, so it costs nothing).
Metaspry re-checks it every day.
Each check compares the score and the rule results with the previous one.
When the score crosses below your threshold, or a required tag that passed at the previous check fails now, the URL is flagged in the app and you get an alert.

Web app Drift monitoring page: three monitored URLs with scores and trend lines, one with a drift badge, and the Slack alerts card — Monitor: each URL with its score, trend and drift badge, then the Slack card.

When an alert is sent

A URL alerts on either of two triggers:

The score crosses below your threshold. The threshold is 80 (“needs work”) by default, or 50 (“failing”) if you pick that for the URL. It has to be a crossing: the previous check was above the threshold and this one is below. A page that loses a point but stays above does not alert, and a page that is already below when you add it is not flagged.
A required tag starts failing. The six required rules are the page title, meta description, og:title, og:description, og:image and being indexable (no noindex). If one of them passed or warned at the previous check and fails now, you get an alert even when the score stays high - a healthy page that loses its og:image drops from 100 to 91 and would never cross 80. Recommended and best-practice rules never alert on their own.

How often you hear about it

Once per newly failing rule. An alert names the required tags that are now failing. The same rule does not alert again for 7 days, even if it flaps between passing and failing; a different rule that starts failing alerts at once.
Once per score drop. Nothing repeats while the page stays below the threshold. The URL recovers when its score is back above the threshold and none of the rules that caused the drift still fail; after that, a new drop alerts again.
Snooze. On a URL’s page you can snooze its alerts for 1, 7 or 30 days. The drift is still shown in the app; if the page is still below when the snooze ends, the next daily check sends the alert.
Delivery. An alert counts as sent once any recipient or channel received it. If every delivery fails, the next daily check tries again.

Who gets the alert

Email goes to the account’s email address. For a workspace, it goes to the owner and every member; viewers are not emailed.
Slack: on the Monitor page, paste a Slack incoming-webhook URL (https://hooks.slack.com/services/...) and press Connect & send test. Metaspry posts a test message and saves the webhook only if Slack accepts it, so a wrong URL fails right away. Alerts then go to Slack as well as email. A failed Slack post is shown on the card, because Slack sends no bounce. Connecting Slack needs Pro personally, or owner or member rights in a paid workspace.

An email names the page and the drop - “Metaspry: Pricing dropped to 62”, or “Metaspry: Homepage: Open Graph image is failing” for a required tag - lists up to 8 changes since the previous check, and links to Monitor. Slack gets the same content.

What you’ll see in the app

The Monitor list shows, per URL:

Score (current, and the change since the previous check)
When it was last checked
A score trend once there are two checks
A drift badge while the URL is flagged, or snoozed

Click into a URL for the detail view:

Score trend with your alert threshold, marking where the page crossed below it and came back
What changed at the last check: the rules that got worse or recovered
A banner saying why it is flagged (“Score dropped past your alert threshold”, or “A required tag started failing” with the tags)
Alert me when: “the score drops below 80, or a required tag fails” or “the score drops below 50, or a required tag fails”
Snooze, and a link to the full scan, where you can compare earlier versions of the page

Tiers

Tier	Monitored URLs	Re-scan frequency
Free	None	-
Pro	Up to 50 URLs	Daily
Team	Up to 250 URLs, shared across the workspace	Daily

Daily checks pause when nobody has opened Monitor in that workspace for 14 days; opening it again resumes them.

Why per-URL

Whole-site change monitors crawl tens of thousands of URLs on a fixed cadence and are priced accordingly. Most teams don’t need that. You need to know if the handful of pages that drive your traffic broke overnight - and that’s exactly what monitoring a URL gives you.

Audit rules - what gets scored, and which rules are required
Compare scans - see exactly which tags changed
Cloud sync - the history these scans write to
Indexability conflicts - the four-signal cross-check