-Update the known_hosts file. For every host listed, search for a gpg
-key for the host in the Web of Trust. If a key is found, any ssh keys
-for the host are removed from the known_hosts file. If the found key
-is acceptable (see KEY ACCEPTABILITY), then the gpg key is converted
-to an ssh key and added to the known_hosts file. If now gpg key is
-found for the host, then nothing is done. If no hosts are specified,
-all hosts listed in the known_hosts file will be processed. If they
-`k' may be used in place of `update-known_hosts'.
+Update the known_hosts file. For each specified host, gpg will be
+queried for a key associated with the host URI (see HOST
+IDENTIFICATION in monkeysphere(5)), optionally querying a keyserver.
+If an acceptable key is found for the host (see KEY ACCEPTABILITY in
+monkeysphere(5)), the key is added to the user's known_hosts file. If
+a key is found but is unacceptable for the host, any matching keys are
+removed from the user's known_hosts file. If no gpg key is found for
+the host, nothing is done. If no hosts are specified, all hosts
+listed in the known_hosts file will be processed. This subcommand
+will exit with a status of 0 if at least one acceptable key was found
+for a specified host, 1 if no matching keys were found at all, and 2
+if matching keys were found but none were acceptable. `k' may be used
+in place of `update-known_hosts'.