Spec Clarification: Client MUST throw *most specific* subclass of WebApplicationException

jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_api.adoc

diff --git a/jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_api.adoc b/jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_api.adoc
index c3333a3..b5d2cd4 100644
--- a/jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_api.adoc
+++ b/jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_api.adoc
@@ -31,3 +31,5 @@
 include::_reactive_clients.adoc[]
 
 include::_executor_services.adoc[]
+
+include::_client_exceptions.adoc[]

jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_exceptions.adoc

diff --git a/jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_exceptions.adoc b/jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_exceptions.adoc
new file mode 100644
index 0000000..3a54764
--- /dev/null
+++ b/jaxrs-spec/src/main/asciidoc/chapters/client_api/_client_exceptions.adoc
@@ -0,0 +1,31 @@
+////
+*******************************************************************
+* Copyright (c) 2022 Eclipse Foundation
+*
+* This specification document is made available under the terms
+* of the Eclipse Foundation Specification License v1.0, which is
+* available at https://www.eclipse.org/legal/efsl.php.
+*******************************************************************
+////
+
+[[client_exceptions]]
+=== Client Exceptions
+
+A method of the JAX-RS Client API that _nominally_ throws `WebApplicationException`
+MUST _actually_ throw the _most specific_ exception subclass for the current response status code,
+unless no such subclass is defined by the JAX-RS API.
+
+Only in the latter case the method MAY throw the `WebApplicationException`
+class directly.
+
+The method MAY throw a direct or indirect subclass of the mandatory exception.
+
+Example: If a response has the status 404, a compliant implementation MUST NOT
+throw `WebApplicationException(404)`, but instead MUST throw `NotFoundException`,
+or a subclass of `NotFoundException`, because the description of `NotFoundException`
+_exactly_ matches the status code 404.
+
+Example: If a response has the status 567, a compliant implementation MUST NOT
+throw `WebApplicationException(567)` but instead MUST throw `ServerErrorException`,
+or a subclass of `ServerErrorException`, because the description of `ServerErrorException`
+_indirectly_ matches the status code 567 by matching the whole 5XX family of codes.

jaxrs-spec/src/main/asciidoc/chapters/providers/_exceptions_providers.adoc

diff --git a/jaxrs-spec/src/main/asciidoc/chapters/providers/_exceptions_providers.adoc b/jaxrs-spec/src/main/asciidoc/chapters/providers/_exceptions_providers.adoc
index 7003855..b36df94 100644
--- a/jaxrs-spec/src/main/asciidoc/chapters/providers/_exceptions_providers.adoc
+++ b/jaxrs-spec/src/main/asciidoc/chapters/providers/_exceptions_providers.adoc
@@ -46,3 +46,4 @@
 Note that the client runtime will only throw an instance of
 `WebApplicationException` (or any of its subclasses) as a result of a
 response from the server with status codes 3xx, 4xx or 5xx.
+See <<client_exceptions>> for more details on `WebApplicationException`.