**WARNING**: This is an advanced feature! It requires prior experience with Matrix and a specific need for using [Matrix Corporal](https://github.com/devture/matrix-corporal). If you're unsure whether you have such a need, you most likely don't.
In short, it's a sort of automation and firewalling service, which is helpful if you're instaling Matrix services in a controlled corporate environment.
See that project's documentation to learn what it does and why it might be useful to you.
If you decide that you'd like to let this playbook install it for you, you'd need to also [set up the Shared Secret Auth password provider module](configuring-playbook-shared-secret-auth.md).
Matrix Corporal operates with a specific Matrix user on your server.
By default, it's `matrix-corporal` (controllable by the `matrix_corporal_reconciliation_user_id_local_part` setting, see above).
No matter what Matrix user id you configure to run it with, make sure that:
- the Matrix Corporal user is created by [registering it](registering-users.md). Use a password you remember, as you'll need to log in from time to time to create or join rooms
- the Matrix Corporal user is joined and has Admin/Moderator-level access to any rooms you want it to manage
As an example: you can create your own configuration files in `/matrix/corporal/config` and they will appear in `/etc/matrix-corporal` in the Docker container. Your configuration (stuff in `matrix_corporal_policy_provider_config`) needs to refer to these files via the local container path `/etc/matrix-corporal`