List all systemd services. Optionally filter by state (running, exited, failed, inactive, all) and by name glob pattern (e.g. 'ssh*', 'cron*'). Defaults to listing all service units.

Get detailed status of a specific systemd service. Returns load state, active state, main PID, memory, CPU, tasks, documentation, and uptime. Accepts service names with or without the .service suffix.

List all systemd services that are currently in a failed/error state. Returns unit name, load state, active state, sub state, and description for each failed service.

Retrieve recent journald log entries for a specific systemd service. Supports configurable line count (up to 5000) and optional priority filtering (emerg, alert, crit, err, warning, notice, info, debug).

Control a systemd service: start, stop, restart, reload, enable, or disable. NOTE: Most actions require root/sudo privileges and will return a permission error if unavailable.