Error message
In the message, %s marks a value that the engine fills in when it raises the error.
The story
Your manifest sets a supervision policy, but one of its values is not a proper number. Let's see what the policy is. Rush supervises processes with a heartbeat, and restarts them within a budget. Those numbers are not buried in the engine, your project declares them, in the manifest, through config. The heartbeat interval must be a whole decimal number above zero. The restart budget must be a whole decimal number, zero or more. So what is refused? A word like fast. A negative number like minus five. A zero for the heartbeat, since a heartbeat that never beats means nothing. Rush stops before it parses any file, because a policy that is silently not applied is a configuration that lies, and a supervisor running on the wrong cadence is a hard bug to find. The message names the manifest, the line, the setting and what you wrote, and the second slot gives the repair. Replace the value with a plain whole number, like one thousand for the heartbeat, and run again.
Text from the Rush engine's error catalogue.