diff --git a/src/applications/drydock/management/DrydockManagementLeaseWorkflow.php b/src/applications/drydock/management/DrydockManagementLeaseWorkflow.php
--- a/src/applications/drydock/management/DrydockManagementLeaseWorkflow.php
+++ b/src/applications/drydock/management/DrydockManagementLeaseWorkflow.php
@@ -20,9 +20,11 @@
             'help' => pht('Set lease expiration time.'),
           ),
           array(
-            'name'      => 'attributes',
-            'param'     => 'name=value,...',
-            'help'      => pht('Resource specification.'),
+            'name' => 'attributes',
+            'param' => 'file',
+            'help' => pht(
+              'JSON file with lease attributes. Use "-" to read attributes '.
+              'from stdin.'),
           ),
         ));
   }
@@ -49,11 +51,20 @@
       }
     }
 
-    $attributes = $args->getArg('attributes');
-    if ($attributes) {
-      $options = new PhutilSimpleOptions();
-      $options->setCaseSensitive(true);
-      $attributes = $options->parse($attributes);
+    $attributes_file = $args->getArg('attributes');
+    if (strlen($attributes_file)) {
+      if ($attributes_file == '-') {
+        echo tsprintf(
+          "%s\n",
+          'Reading JSON attributes from stdin...');
+        $data = file_get_contents('php://stdin');
+      } else {
+        $data = Filesystem::readFile($attributes_file);
+      }
+
+      $attributes = phutil_json_decode($data);
+    } else {
+      $attributes = array();
     }
 
     $lease = id(new DrydockLease())