If a service is associated with a shared or reseller hosting account, or a managed server, it is not possible to have this functionality. Resource management is our responsibility in any of the cases. If we identify excessive CPU usage and if it is possible to reduce that usage by optimizing the mysql server, we solve it without worrying the customer.
In order for us to manage a server with custom tools (or other software) which would allow you to receive CPU usage alerts, it is necessary to purchase an unmanaged server where you will have root access and can install and configure whatever you want. If you require assistance with an unmanaged service, you can purchase a professional support plan from which you will have a team at your disposal to implement any solution at an administrative or technical level.
Alternatively, you can occasionally request a quote from which you would only pay once for the software installation, configuration, hours of training or hours of support associated with the third-party tool.