clarify wording even more

Author: devalog

fern/products/api-def/ferndef-pages/types.mdx

@@ -282,7 +282,7 @@ interface Person {
 
 ### Validating types
 
-You can add validation constraints to your types (both aliases and references) to ensure data integrity. These validation constraints are not included in generated SDKs – actual validation is deferred to the server.
+You can add validation constraints to your types (both aliases and references) to ensure data integrity. These validation constraints exist in your API definition and are enforced by your server, but the generated client SDKs don't include validation logic.
 
 <CodeBlock title="Fern Definition">
 ```yaml {8-11, 15-17}