diff --git a/README.md b/README.md
index 529d22a..846dbcb 100644
--- a/README.md
+++ b/README.md
@@ -271,6 +271,7 @@ Here's a sample context object:
             "parameters": {
                 "name": "parameterName",
                 "type": "parameterType",
+                "isOptional": true
             }
         }
     ]