Dokka not scanning Kotlin files when called from command line

When calling Dokka from the command-line it won’t scan Kotlin files. It does work with Maven but my aim is to create a documentation over all a I created JSON file with all the sourceRoots needed. However only Java files are scanned. I wonder if an pluginsClasspath is missing. Currently I use:

    "pluginsClasspath": [
        "/Users/Shared/Work/Repositories/Local/org/jetbrains/dokka/dokka-base/1.9.10/dokka-base-1.9.10.jar",
        "/Users/Shared/Work/Repositories/Local/org/jetbrains/kotlinx/kotlinx-html-jvm/0.9.1/kotlinx-html-jvm-0.9.1.jar",
        "/Users/Shared/Work/Repositories/Local/org/jetbrains/dokka/analysis-kotlin-descriptors/1.9.10/analysis-kotlin-descriptors-1.9.10.jar",
        "/Users/Shared/Work/Repositories/Local/org/freemarker/freemarker/2.3.31/freemarker-2.3.31.jar"
    ],