diff --git a/schema/metadata/entityDefs.json b/schema/metadata/entityDefs.json
index 32ce4b1548..8f334a00a5 100644
--- a/schema/metadata/entityDefs.json
+++ b/schema/metadata/entityDefs.json
@@ -245,6 +245,25 @@
                         }
                     }
                 },
+                {
+                    "if": {
+                        "properties": {
+                            "type": {
+                                "anyOf": [
+                                    {"const": "array"}
+                                ]
+                            }
+                        }
+                    },
+                    "then": {
+                        "properties": {
+                            "noEmptyString": {
+                                "type": "boolean",
+                                "description": "Don't allow empty string."
+                            }
+                        }
+                    }
+                },
                 {
                     "if": {
                         "properties": {
@@ -564,6 +583,27 @@
                         }
                     }
                 },
+                {
+                    "if": {
+                        "properties": {
+                            "type": {
+                                "anyOf": [
+                                    {"const": "link"},
+                                    {"const": "linkMultiple"},
+                                    {"const": "linkOne"}
+                                ]
+                            }
+                        }
+                    },
+                    "then": {
+                        "properties": {
+                            "entity": {
+                                "type": "string",
+                                "description": "An entity type. To be specified if there's no corresponding link defined."
+                            }
+                        }
+                    }
+                },
                 {
                     "if": {
                         "properties": {