Enable it if you did not install with --enable:
hermes plugins enable ponytailRestart Hermes or the gateway after enabling.
In shared gateways, restrict /ponytail to trusted users with Hermes slash-command access controls; runtime mode is process-local.
Commands:
/ponytail [lite|full|ultra|off]/ponytail-review [target]/ponytail-audit [target]/ponytail-debt/ponytail-gain/ponytail-help
Bundled skills are available as ponytail:ponytail, ponytail:ponytail-review, ponytail:ponytail-audit, ponytail:ponytail-debt, ponytail:ponytail-gain, and ponytail:ponytail-help.