diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 8ec47fcffef..034b7022e82 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -283,7 +283,7 @@ namespace ts {
         {
             name: "allowSyntheticDefaultImports",
             type: "boolean",
-            description: Diagnostics.Allow_default_imports_from_modules_with_no_default_export
+            description: Diagnostics.Allow_default_imports_from_modules_with_no_default_export_This_does_not_affect_code_emit_just_typechecking
         },
         {
             name: "allowJs",
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 9646353d8f8..882fd41d6d4 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2109,7 +2109,7 @@
         "category": "Message",
         "code": 6010
     },
-    "Allow default imports from modules with no default export": {
+    "Allow default imports from modules with no default export. This does not affect code emit, just typechecking.": {
         "category": "Message",
         "code": 6011
     },