diff --git a/runtime/syntax/json.yaml b/runtime/syntax/json.yaml
index 6d8408333b..f69a304bf6 100644
--- a/runtime/syntax/json.yaml
+++ b/runtime/syntax/json.yaml
@@ -25,3 +25,15 @@ rules:
 
     - statement: "\\\"(\\\\\"|[^\"])*\\\"[[:space:]]*:\"  \"'(\\'|[^'])*'[[:space:]]*:"
     - constant: "\\\\u[0-9a-fA-F]{4}|\\\\[bfnrt'\"/\\\\]"
+
+    - comment:
+        start: "//"
+        end: "$"
+        rules:
+            - todo: "(TODO|XXX|FIXME):?"
+
+    - comment:
+        start: "/\\*"
+        end: "\\*/"
+        rules:
+            - todo: "(TODO|XXX|FIXME):?"