Do you have an API call you can run that will "verify" that the API is up and running? You could run that first via a block until done tool and then if it's good it will continue with your workflow...
@JohnBell You can use the message tool to 'look for a message' as a result from the API call. You can have it error out within the message tool and set the runtime settings to 'cancel running workflows on error'.
@JohnBell Here you go.