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About the scanner

Know what your scan
does and does not tell you.

How to read a Wexlo report: what comes from the rule engine, the software that tests the technical rules, and what a person still has to assess.

  1. TestingFind what needs attention
  2. FixGive your developer a task
  3. RetestCheck the result
  4. Keep evidenceRecord the outcome

A change or a release? The cycle starts again.

From loading to finding.

  1. Loading

    A real browser opens every page, just as a visitor would.

  2. Checks

    Axe-core tests against WCAG 2.2 level A and AA, on a desktop and a mobile viewport.

  3. Determine

    The rule engine determines what counts as a finding. Not us, and not the AI.

  4. Summarising

    With a paid scan, an AI layer writes the summary and the explanation with it, marked in the report as AI-written. With the free scan, AI only writes the example fix in the email, marked as AI-assisted.

  5. Delivery

    You get the findings back exactly as the rule engine established them.

Who decides what, precisely.

The rule engine determines

  • Whether an element breaches a WCAG criterion
  • The criterion a finding is logged against
  • Every measurement, such as a contrast value

The AI layer writes

  • The summary at the top of a report
  • Plain-language explanation for a finding
  • Never the finding itself

AI text is always marked as AI-written; the finding itself is not, because that comes from the rule engine.

What a scan never fills in.

This remains human work, on top of every scan and on top of every overlay.

  • The scan establishes
    Whether there is alt text, and whether it is obviously weak
    A person assesses
    Whether that text conveys the purpose of the image
  • The scan establishes
    Whether the headings are technically valid
    A person assesses
    Whether the order reads logically
  • The scan establishes
    Vague link text such as "click here" or "read more"
    A person assesses
    Whether a link text is clear in its context
  • The scan establishes
    Whether a field technically has a label
    A person assesses
    Whether the label and the error message are understandable
  • The scan establishes
    A tab run-through, with clear keyboard traps
    A person assesses
    Whether everything works predictably with the keyboard alone

Every report names these points separately, with what needs doing.

What you do not need.

  • No installation on your server
  • No widget or script on your website
  • No access to your codebase
  • No account needed for a free scan

How to allow us in if your site blocks bots.

Recognise us by the User-Agent
We identify ourselves as WexloScanner/1.0 (+https://wexlo.eu/scanner-info). We never pose as an ordinary visitor: no spoofed headers, no imitated mouse behaviour, no proxy to look different. What you see in your logs is what we are.
Allowlist on that name, not on an IP address
We run from the Frankfurt region of Fly.io, and those apps share a pool of outgoing IP addresses rather than one fixed address. So we cannot give a narrow IP range. The User-Agent above does not change even when the IP address does, so that is the durable rule.
At Cloudflare, it's a WAF rule
Create a rule in Cloudflare under Security, WAF, Custom rules:
Expression: http.user_agent contains "WexloScanner"
Action: Skip (or Allow)
Bot Fight Mode and Super Bot Fight Mode are assessed separately, so check those too if a scan still gets challenged.
http.user_agent contains "WexloScanner"

Another provider or your own firewall
If you do not use Cloudflare but another provider or your own firewall, check that service's documentation for how to let traffic with this User-Agent through. If you get stuck, get in touch with us.
A robots.txt rule is not a firewall rule
robots.txt tells crawlers what you would prefer. It will not get us through a WAF. If there is a block in place, you need the rule above.

Think a finding is wrong?

If you think a finding is wrong, read how to report it. Reports are checked by hand, because a rule engine can miss a genuine edge case.

Test one page of your own site.

Free and without an account. Rather ask a question first? Use the contact form.