While both Universal API and Universal Automation provide REST API support, Universal API is much more customizable in the endpoints that you define. You can specify and route, method and script block to be executed with Universal API. Unlike Universal Automation, each job is not audited with Universal API. You will not be able to see each request that came in, the output or the result of the execution. Unlike Universal Automation, Universal API is designed for maximum speed and will not start a new PowerShell process with each execution.