service/documentation.md

@@ -149,6 +149,13 @@ Or just:
 typos, but there's over a hundred of them at the time of writing, so
 we only fail on changed files for now.
 
+This should yield very few false positives, but if we do find some, we
+could start an "exclude file" (`exclude-file = PATH` in the
+`.codespellrc`) that would list the actual lines of text to exclude.
+
+Some file patterns are skipped in the `.codespellrc` (currently
+`*.json`, `*.csv`, and the entire `.git` directory).
+
 ## Accepting merge requests on wikis
 
 It's possible to work around the [limitation of Wiki permissions](https://gitlab.torproject.org/tpo/tpa/gitlab/-/issues/76)