fix: note on schema behavior

Author: logaretm

docs/src/pages/guide/migration.mdx

@@ -7,14 +7,23 @@ order: 10
 
 # Migrating from v4 to v5
 
-vee-validate v5 is a major release yet it does not introduce any breaking changes except when it comes to validation schemas. This is because vee-validate v5 now supports [standard schema](https://standardschema.dev/) libraries like zod, valibot, yup, and more.
+vee-validate v5 is a major release that brings support to [standard schema](https://standardschema.dev/) libraries like zod, valibot, yup, and more.
 
 This means most of the companion packages like `@vee-validate/zod`, `@vee-validate/yup`, `@vee-validate/valibot` are no longer needed and are now deprecated.
 
 ## Changes to Nuxt Module
 
 The nuxt module won't suggest installing any packages anymore since most providers that were supported in v4 are now supported in v5 via standard schema API.
 
+## Changes to schema behavior
+
+Since vee-validate v5 is considered schema agnostic, you lose some features that were previously possible with each dedicated validation provider.
+
+- Resolving `required` meta flag is no longer supported from schemas.
+- Using defaults to initialize the form values is no longer supported from schemas.
+
+While these features are critical to many apps, the standard schema spec does not provide a way to do that at the moment. Alternatives are being considered via external packages at the moment.
+
 ## Replace Typed Schema calls
 
 Typed schemas were a way for vee-validate v4 to support a common interface for multiple validation providers. However, there is a community driven package called [standard schema](https://standardschema.dev/) that provides a common interface for multiple validation providers that is becoming very popular and is already supported by the most popular validation providers.