The plugin needs the [[!cpan Net::OpenID::Consumer]] perl module.
Version 1.x is needed in order for OpenID v2 to work.
-The [[!cpan LWPx::ParanoidAgent]] perl module is used if available, for
-added security. Finally, the [[!cpan Crypt::SSLeay]] perl module is needed
+The [[!cpan LWPx::ParanoidAgent]] Perl module is strongly recommended.
+The [[!cpan LWP]] module can also be used, but is susceptible to
+server-side request forgery.
+
+The [[!cpan Crypt::SSLeay]] Perl module is needed
to support users entering "https" OpenID urls.
This plugin is enabled by default, but can be turned off if you want to
only use some other form of authentication, such as [[passwordauth]].
+
+## options
+
+These options do not normally need to be set, but can be useful in
+certain setups.
+
+* `openid_realm` can be used to control the scope of the openid request.
+ It defaults to the `cgiurl` (or `openid_cgiurl` if set); only allowing
+ ikiwiki's [[CGI]] to authenticate. If you have multiple ikiwiki instances,
+ or other things using openid on the same site, you may choose to put them
+ all in the same realm to improve the user's openid experience. It is an
+ url pattern, so can be set to eg "http://*.example.com/"
+
+* `openid_cgiurl` can be used to cause a different than usual `cgiurl`
+ to be used when doing openid authentication. The `openid_cgiurl` must
+ point to an ikiwiki [[CGI]], and it will need to match the `openid_realm`
+ to work.
+
+## troubleshooting
+
+See [[plugins/openid/troubleshooting]] for a number of issues that may
+need to be addressed when setting up ikiwiki to accept OpenID logins reliably.
+
+## delegation
+
+This plugin does not take care of doing the "server" part of the
+OpenID protocol, only the "client" part. In other words, it allows
+users to login to your site through OpenID, but is not in itself an
+OpenID provider.
+
+It is possible, however, to use your Ikiwiki site as a delegation
+point to another OpenID provider. For this, use the
+[[ikiwiki/directive/meta/]] directive with the `openid` parameter.