This tool reflows comments in KDoc; either on a file or recursively over nested folders, as well as an IntelliJ IDE plugin where you can reflow the current comment around the cursor. Here's an example ...
Other supported languages: Haskell, Agda, Erlang, Groovy, Ruby, Elixir, Objective-C, PHP, SQL, Apex language, Bash, C# Razor Pages, GLSL (the OpenGL Shading Language ...