Missing @param tag for parameters in puppet strings format

The command puppet strings generate produce following output :

[warn]: Missing @param tag for parameter 'db_host' near manifests/init.pp:28.
[warn]: Missing @param tag for parameter 'db_port' near manifests/init.pp:28.
[warn]: Missing @param tag for parameter 'db_name' near manifests/init.pp:28.
[warn]: Missing @param tag for parameter 'db_for_tests_name' near manifests/init.pp:28.
[warn]: Missing @param tag for parameter 'db_user_name' near manifests/init.pp:28.
[warn]: Missing @param tag for parameter 'system_username' near manifests/init.pp:28.
[warn]: Missing @param tag for parameter 'debug' near manifests/init.pp:28.