There is now detailed documentation available on the official docs.parity-deploy with the aura parameter seems to deploy a Validator Set contract.
The details on how to add/remove validators with Validator Set contracts are given here. Essentially, each node has a set of validators which it supports. Validators are part of the network as long as at least half of all nodes support them.
By using the function
addValidator of the RelaySet contract (part of the Validator Set contracts), you can add a validator, as shown in detail here.
You can remove support and report misbehaviors. An example for this is given here. Essentially, a Dapp monitors other nodes and if they are down, sends a transaction to the
reportBenign function of the RelaySet contract. This function must be called twice to fully remove support - this way a node may change its mind after the first report by calling
Initially you need to find the address of the contract to conduct any transactions. According to parity-deploy documentation, you should be able to find the relevant addresses in the deployment folder's