Adding docs
diff --git a/openstack/identity/v2/extensions/admin/roles/requests.go b/openstack/identity/v2/extensions/admin/roles/requests.go
index ffd697e..4765534 100644
--- a/openstack/identity/v2/extensions/admin/roles/requests.go
+++ b/openstack/identity/v2/extensions/admin/roles/requests.go
@@ -6,6 +6,8 @@
 	"github.com/rackspace/gophercloud/pagination"
 )
 
+// List is the operation responsible for listing all available global roles
+// that a user can adopt.
 func List(client *gophercloud.ServiceClient) pagination.Pager {
 	createPage := func(r pagination.PageResult) pagination.Page {
 		return RolePage{pagination.SinglePageBase(r)}
@@ -13,6 +15,9 @@
 	return pagination.NewPager(client, rootURL(client), createPage)
 }
 
+// AddUserRole is the operation responsible for assigning a particular role to
+// a user. This is confined to the scope of the user's tenant - so the tenant
+// ID is a required argument.
 func AddUserRole(client *gophercloud.ServiceClient, tenantID, userID, roleID string) UserRoleResult {
 	var result UserRoleResult
 
@@ -24,6 +29,9 @@
 	return result
 }
 
+// DeleteUserRole is the operation responsible for deleting a particular role
+// from a user. This is confined to the scope of the user's tenant - so the
+// tenant ID is a required argument.
 func DeleteUserRole(client *gophercloud.ServiceClient, tenantID, userID, roleID string) UserRoleResult {
 	var result UserRoleResult