diff --git a/schema-docs.md b/schema-docs.md
index 223025b3..921d7cb2 100644
--- a/schema-docs.md
+++ b/schema-docs.md
@@ -4988,7 +4988,9 @@ Usages:
 | `composite_list` | supported | unknown | supported | unknown |
 </details>
 
-No constraints.
+Constraints: 
+
+* `additionalProperties`: `false`
 
 Usages:
 
@@ -5002,6 +5004,7 @@ Usages:
   "$id": "https://opentelemetry.io/otelconfig/propagator.json",
   "$schema": "https://json-schema.org/draft/2020-12/schema",
   "type": "object",
+  "additionalProperties": false,
   "properties": {
     "composite": {
       "type": "array",
diff --git a/schema/propagator.json b/schema/propagator.json
index 7283170f..322ac50a 100644
--- a/schema/propagator.json
+++ b/schema/propagator.json
@@ -2,6 +2,7 @@
     "$id": "https://opentelemetry.io/otelconfig/propagator.json",
     "$schema": "https://json-schema.org/draft/2020-12/schema",
     "type": "object",
+    "additionalProperties": false,
     "properties": {
         "composite": {
             "type": "array",