[polkit](https://www.freedesktop.org/wiki/Software/polkit/) is a software framework to handle privileges of processes.
In LXQt it is e. g. used to extend the privileges of the GUI tools of [lxqt-admin](https://github.com/lxde/lxqt-admin/). These are launched by a regular user. But in order to apply the settings they deal with root privileges are needed and acquired via polkit.
Among the various components of polkit the authentication agent is the one to query the user for credentials by dialogue windows like this one of lxqt-policykit.
![lxqt-policykit: GUI](lxqt-policykit_gui.png)
While there's only a single implementation of all other polkit components various different authentication agents are provided by the various desktop environments. Basically these can be used interchangeably, that is lxqt-policykit can be used in an LXDE session or lxpolkit, the authentication agent of LXDE, can be used in an Xfce session. Most of the time it's better to use the implementation provided by a distinct desktop environment as it integrates better, though.
Technically, lxqt-policykit is just a single binary `lxqt-policykit-agent` which is running as [LXQt Module](https://github.com/lxde/lxqt-session#lxqt-modules) and launching the GUI on demand.
Runtime dependencies are polkit-qt5 and [liblxqt](https://github.com/lxde/liblxqt).
Additional build dependencies are CMake and optionally Git to pull latest VCS checkouts. The localization files were outsourced to repository [lxqt-l10n](https://github.com/lxde/lxqt-l10n) so the corresponding dependencies are needed, too. Please refer to this repository's `README.md` for further information.
Like all LXQt Modules `lxqt-policykit-agent` can be adjusted from section "Basic Settings" in configuration dialogue [LXQt Session Settings](https://github.com/lxde/lxqt-session#lxqt-session-settings) of [lxqt-session](https://github.com/lxde/lxqt-session).