diff --git a/htmlSanityCheck-cli/src/main/groovy/org/aim42/htmlsanitycheck/cli/Main.groovy b/htmlSanityCheck-cli/src/main/groovy/org/aim42/htmlsanitycheck/cli/Main.groovy
index 2f5d0c6b..354375fe 100644
--- a/htmlSanityCheck-cli/src/main/groovy/org/aim42/htmlsanitycheck/cli/Main.groovy
+++ b/htmlSanityCheck-cli/src/main/groovy/org/aim42/htmlsanitycheck/cli/Main.groovy
@@ -5,9 +5,14 @@ import org.aim42.htmlsanitycheck.Configuration
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 import picocli.CommandLine
+import picocli.CommandLine.Parameters
 import picocli.CommandLine.Command
 import picocli.CommandLine.Option
 
+import java.nio.file.Files
+import java.nio.file.Path
+import java.nio.file.Paths
+
 // see end-of-file for license information
 
 @Command(name = "hsc", mixinStandardHelpOptions = true, version = "hsc 2.0.0",
@@ -23,30 +28,39 @@ class Main implements Runnable {
 //                "-r resultsDir""")
 //    }
 
-    @Option(names = ["-s", "--sourceDir"], description = "Source Directory")
-    String sourceDirectoryName
-
-    @Option(names = ["-f", "--sourceFile"], description = "Source Directory", arity = "*")
-    String[] sourceFileNames
-
     @Option(names = ["-r", "--resultsDir"], description = "Results Directory")
     String resultsDirectoryName = "/tmp/results"
 
+    @Parameters(arity = "1..*", description = "at least one File")
+    File[] files
+
     static void main(String[] args) {
         Main app = new Main()
         CommandLine cmd = new CommandLine(app)
         cmd.execute(args)
     }
 
+    private List<File> findFiles(File directory) throws IOException {
+        List<File> files = new ArrayList<>()
+        Files.walk(Paths.get(directory.getPath()))
+                .filter(Files::isRegularFile)
+                .filter(path -> path.getFileName().endsWith(".html"))
+                .forEach(files::add)
+        return files
+    }
+
     void run() {
         var configuration = new Configuration()
 
         var resultsDirectory = new File(resultsDirectoryName)
 
-        configuration.addConfigurationItem(Configuration.ITEM_NAME_sourceDir, new File(sourceDirectoryName))
         configuration.addConfigurationItem(Configuration.ITEM_NAME_sourceDocuments,
-                sourceFileNames.collect {filename ->
-                    return new File(filename)
+                files.collect { file ->
+                    if (file.isDirectory()) {
+                        return findFiles(file)
+                    } else {
+                        return new File(file)
+                    }
                 }
         )
         configuration.addConfigurationItem((Configuration.ITEM_NAME_checkingResultsDir), resultsDirectory)
diff --git a/htmlSanityCheck-core/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy b/htmlSanityCheck-core/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy
index 98a5bbb0..8f739942 100644
--- a/htmlSanityCheck-core/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy
+++ b/htmlSanityCheck-core/src/main/groovy/org/aim42/htmlsanitycheck/Configuration.groovy
@@ -228,13 +228,13 @@ class Configuration {
         Set<String> srcDocs = getConfigItemByName(Configuration.ITEM_NAME_sourceDocuments)
 
         // cannot check if source director is null (= unspecified)
-        if ((srcDir == null)) {
-            throw new MisconfigurationException("source directory must not be null")
-        }
-
-        if ((!srcDir.exists())) {
-            throw new MisconfigurationException("given sourceDir $srcDir does not exist.")
-        }
+//        if ((srcDir == null)) {
+//            throw new MisconfigurationException("source directory must not be null")
+//        }
+//
+//        if ((!srcDir.exists())) {
+//            throw new MisconfigurationException("given sourceDir $srcDir does not exist.")
+//        }
 
         // cannot check if both input params are null
         if (srcDocs == null) {