diff --git a/http/swagger.yml b/http/swagger.yml
index 9aa6b26400..283160209e 100644
--- a/http/swagger.yml
+++ b/http/swagger.yml
@@ -6431,6 +6431,8 @@ components:
           enum: ["map"]
         values:
           type: object
+          additionalProperties:
+            type: string
     QueryVariableProperties:
       properties:
         type: