@Schema field-level description ignored when using custom type with $ref #2723

I'm encountering an issue with Springdoc when using custom types in DTOs for generating OpenAPI documentation. Specifically, I have a field in my DTO that uses a custom type (e.g., CustomLongId), and I'm trying to define a field-specific description with the @Schema annotation. However, the generated OpenAPI documentation only shows a reference to the schema ($ref: #/components/schemas/CustomLongId) and ignores the field-level description that I provided.

Here’s a minimal example of the problem:

Code Example:

public class SharedCustomIdRequestDto {

@Nullable
@Schema(description = "request dto custom long id")
@Valid
private CustomLongId requestCustomLongId;

}
And the custom type:

@Schema(description = "Custom Long id")
public class CustomLongId {
private String value;
}

In the generated OpenAPI documentation, the field requestCustomLongId is represented as a $ref to the CustomLongId schema, but the field-specific description ("request dto custom long id") is lost.

Expected Behavior:
The field-specific description provided in the @Schema annotation ("request dto custom long id") should be shown in the generated OpenAPI documentation for the requestCustomLongId field.
Actual Behavior:
The generated schema references #/components/schemas/CustomLongId, and the field-specific description is not included.

Example of the Generated Schema:

"requestCustomLongId": {
"$ref": "#/components/schemas/CustomLongId",
"description": null
}

Additional Information:
Springdoc Version: 2.6.0
Spring Boot Version: 3.3.3
Java Version: 21

Can you please provide a way to ensure that field-level descriptions are respected even when using a custom type like CustomLongId?
Ideally, the field-level description should visible in generated documentation.

I asked the question in springdoc-openapi repository but they mentioned it is related to swagger-core not springdoc-openapi. Please see https://github.com/springdoc/springdoc-openapi/issues/2723
I tried to solve it via PropertyCustomizer as workaround but still couldn't find description in the provided PropertyCustomizer parameters as input.

Thank you for your support!
Ramazan

Reproduce the minimal Java DTO example with Spring Boot 3.3.3 and inspect the schema-generation path used when an annotated field resolves to a $ref. Confirm the behavior with a focused regression test, then verify that the field-level description is retained alongside the referenced CustomLongId schema.