@end defopt
@defopt url-user-agent
-The User Agent string used for sending HTTP/HTTPS requests. The value
-should be a string or a function of no arguments that returns a
-string. The default value is @w{@samp{User-Agent: @var{package-name}
-URL/Emacs}}, where @var{package-name} is the value of
+The User Agent string used for sending @acronym{HTTP}/@acronym{HTTPS}
+requests. The value should be @code{nil}, which means that no
+@samo{User-Agent} header is generated, @code{default}, which means
+that a string is generated based on the setting of
+@code{url-privacy-leve}, a string or a function of no arguments that
+returns a string.
+
+The default is @code{default}, which means that the
+@w{@samp{User-Agent: @var{package-name} URL/Emacs}} string will be
+generated, where @var{package-name} is the value of
@code{url-package-name} and its version, if they are non-@code{nil}.
@end defopt
*** The URL package now support https over proxies supporting CONNECT.
----
++++
*** `url-user-agent' now defaults to `default', and the User-Agent
string is computed dynamically based on `url-privacy-level'.