Address comments

aep/general/0217/aep.md.j2

@@ -35,16 +35,18 @@ message ListBooksResponse {
 
 {% endtabs %}
 
-- The field **must** be a repeated string/string array, and **should** be named
+- The field **must** be a repeated string/string array, and **must** be named
   `unreachable`.
 - The field **must** be set to the paths of the resources which are the cause
   of the issue, such as the parent or individual resources that could not be
   reached. The objects listed as unreachable **may** be _parents_ (or higher
   ancestors) rather than the individual resources being requested. For example,
   if a location is unreachable, the location is listed.
   - The response **must not** provide any other information about the issue,
-    such as error details or codes. To discover what the underlying issue is,
-    users **should** send a more specific request.
+    such as error details or codes. Toe enable users to discover what the
+    underlying issue is, APIs **should** provide an API method (which may be
+    just the standard `Get` method) method that provides more specific
+    information.
   - The service **must** provide a way for the user to get an error with
     additional information, and **should** allow the user to repeat the
     original call with more restrictive parameters in order to do so.