Accessibility (WCAG) Monitoring

An Accessibility monitor loads your page in a real headless browser on every check and audits it with axe-core — the engine behind most accessibility testing tools, including Lighthouse's Accessibility score — against the WCAG level you choose.

Each check records:

• Violated rules by impact — critical, serious, moderate and minor (axe-core's own severity levels), charted over time.
• Affected elements — how many elements on the page fail at least one rule.
• The rules themselves — up to 25 per check, most severe first, each with its WCAG success criteria (e.g. 1.4.3), example element selectors and a link to axe-core's explanation of how to fix it.

What it doesn't do: automated checks find roughly a third to half of real WCAG issues — things like meaningful alt text, logical focus order or understandable error messages still need a human. A clean result means "no automatically detectable violations", not full WCAG conformance.

Availability

Requires a plan with Accessibility Monitoring (Professional and above) — every check runs a full browser page load.

How it works

curl -X POST https://api.monsphere.com/api/v1/organizations/{orgId}/monitors \
  -H "X-Api-Key: msph_live_..." -H "Content-Type: application/json" \
  -d '{
    "name": "Homepage Accessibility",
    "type": "accessibility",
    "target": "https://example.com",
    "intervalSeconds": 3600,
    "config": {
      "accessibilityStandard": "wcag21aa",
      "accessibilityFailImpact": "serious",
      "accessibilityMaxViolations": 2
    }
  }'

• accessibilityStandard — wcag2a, wcag2aa, wcag21aa (default) or wcag22aa. Each level includes every level below it.
• accessibilityFailImpact — which violations count toward going down: critical (default), serious, moderate or minor — each including everything more severe.
• accessibilityMaxViolations — how many violated rules at that level are allowed (default 0). Set it to today's count to alert only on regressions; a negative value means "track only, never go down on violations".
• The monitor goes down when more rules than allowed are violated, or when the page can't be loaded or audited — e.g. 3 rule(s) at serious impact or above violated, 2 allowed.
• Checks run at most every 15 minutes.

How it runs

The page is loaded in a sandboxed headless Chromium, with the same network guard every browser-based check uses (it can't reach private or internal addresses), and audited a couple of seconds after load so client-rendered content is included. The axe-core version is fixed and bundled with MonSPHERE — never fetched from a CDN at check time — so results only change when your page does. There's no region to pick — checks run from the central worker.

Bot protection and error pages: if the site serves a bot-protection challenge (such as Cloudflare's "Just a moment...") or the page returns an HTTP error status, the page isn't audited — the monitor goes down and says why, instead of recording results for the challenge or error page. Allowlist MonSPHERE's checks in your bot protection, or monitor a page that isn't behind it.