a tool that can check markdown files

service/documentation.md

@@ -381,6 +381,8 @@ GitLab wikis.
  * [languagetool](https://www.languagetool.org/): Grammar, Style and Spell Checker
  * [anorack](https://github.com/jwilk/anorack): spots errors based on phonemes
  * [redpen](https://redpen.cc/): huge JAR, can be noisy
+ * [linkchecker](https://github.com/linkchecker/linkchecker/): can check links in HTML (anarcat is one of the
+   maintainers), has many alternatives, see for example [lychee](https://github.com/lycheeverse/lychee)
 
 See also [this LWN article](https://lwn.net/Articles/822969/).