diff --git a/lib/rbs/cli.rb b/lib/rbs/cli.rb
index c645c2deb..793f080bf 100644
--- a/lib/rbs/cli.rb
+++ b/lib/rbs/cli.rb
@@ -322,6 +322,7 @@ def run_ancestors(args, options)
         end
       else
         stdout.puts "Cannot find class: #{type_name}"
+        return 1
       end
 
       0
@@ -380,6 +381,7 @@ def run_methods(args, options)
         end
       else
         stdout.puts "Cannot find class: #{type_name}"
+        return 1
       end
 
       0