SLING-10294 documenting expected return codes
diff --git a/src/main/java/org/apache/sling/cli/impl/Command.java b/src/main/java/org/apache/sling/cli/impl/Command.java
index b254c69..9e0ba6b 100644
--- a/src/main/java/org/apache/sling/cli/impl/Command.java
+++ b/src/main/java/org/apache/sling/cli/impl/Command.java
@@ -20,6 +20,9 @@
/**
* Marker interface for {@code Commands} supported by the Apache Sling Committer CLI.
+ * The {@code call} method is expected to return on of the exit codes found in {@code CommandLine.ExitCode}
+ *
+ * @see picocli.CommandLine.ExitCode
*/
public interface Command extends Callable<Integer> {
