Chimney TopDigital Services

Accessibility scanner

ChimneyTopA11yBot

ChimneyTopA11yBot is the crawler of the Plain-English Accessibility Scanner, a product of Chimney Top Digital Services. It loads web pages in a browser and runs automated accessibility checks on them, then reports the problems it finds in plain English to the person who asked for the scan.

When it visits a site

It visits a site only when someone asks the scanner to check it:

  • a one-time free scan from our website, where the person must confirm they own the site or have the owner's permission to scan it (at most 3 pages), or
  • a scan or monthly rescan for a customer who has proved they own the site (at most 5 to 200 pages, depending on their plan).

It identifies itself with this user agent:

ChimneyTopA11yBot/1.0 (+https://chimneytopdigital.com/accessibility-scanner/bot; accessibility audit)

How it behaves

  • It reads your robots.txt first and obeys it. Rules for ChimneyTopA11yBot apply; otherwise the rules for * do. If robots.txt cannot be read because of a server error or timeout, it does not crawl at all.
  • It waits at least 1 second between pages and honours a Crawl-delay of up to 10 seconds.
  • It stays on the site it was asked to check and loads a capped number of pages.
  • It only reads pages. It does not log in, fill in or submit forms, or send anything other than GET and HEAD requests.
  • It runs on Amazon Web Services with addresses that change, so identify it by its user agent rather than by IP address.

How to block it

To stop ChimneyTopA11yBot from crawling your whole site, add this to the robots.txt file at the root of your site:

User-agent: ChimneyTopA11yBot
Disallow: /

To keep it out of some sections only, or to slow it down:

User-agent: ChimneyTopA11yBot
Disallow: /checkout/
Disallow: /account/
Crawl-delay: 5

The change applies to the next scan; each scan reads robots.txt again.

Contact

If you did not expect a scan of your site, or you want us to stop scanning it, email support@chimneytopdigital.com with your site's address and roughly when you saw the visits. We act on every complaint from website owners and can refuse further scans of a site.