Richard,
Not sure if this is what you are after.
But you can run gmu help on most items.
For example
gmu /? will produce 1 set of help.
gmu list /? will produce another set of help.
Below gives me all policies.
GMU\gmu9.2>gmu.bat list -t SERVICE -h <GatewayHost> -u admin -plaintextPassword 7layer --trustCertificate --trustHostname
GMU optons for -t
-t,--type <type>
Entity type to query.[ASSERTION_ACCESS, CASSANDRA_CONFIGURATION, CLUSTER_PROPERTY, CUSTOM_KEY_VALUE_STORE, EMAIL_LISTENER, ENCAPSULATED_ASSERTION, FIREWALL_RULE, FOLDER, GENERIC, GROUP, HTTP_CONFIGURATION, ID_PROVIDER_CONFIG, INTERFACE_TAG, JDBC_CONNECTION, JMS_ENDPOINT, POLICY, POLICY_ALIAS, POLICY_BACKED_SERVICE, RBAC_ROLE, RESOURCE_ENTRY, REVOCATION_CHECK_POLICY, SAMPLE_MESSAGE, SCHEDULED_TASK, SECURE_PASSWORD, SECURITY_ZONE, SERVER_MODULE_FILE, SERVICE, SERVICE_ALIAS, SITEMINDER_CONFIGURATION, SOLUTION_KIT, SSG_ACTIVE_CONNECTOR, SSG_CONNECTOR, SSG_KEY_ENTRY, TRUSTED_CERT, USER, WORK_QUEUE]
Thanks..