@Target(value=TYPE)
@Retention(value=RUNTIME)
public @interface JacksonStdImpl

Marker interface used to indicate implementation classes (serializers, deserializers etc) that are standard ones Jackson uses; not custom ones that application has added. It can be added in cases where certain optimizations can be made if default instances are uses; for example when handling conversions of "natural" JSON types like Strings, booleans and numbers.