diff --git a/core/src/main/java/hudson/FilePath.java b/core/src/main/java/hudson/FilePath.java
index 719b01db93..c241baeb83 100644
--- a/core/src/main/java/hudson/FilePath.java
+++ b/core/src/main/java/hudson/FilePath.java
@@ -485,6 +485,8 @@ public final class FilePath implements Serializable {
      *
      * @param includes
      *      See {@link FileSet} for the syntax. String like "foo/*.zip".
+     * @return
+     *      can be empty but always non-null.
      */
     public FilePath[] list(final String includes) throws IOException, InterruptedException {
         return act(new FileCallable<FilePath[]>() {