Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read-only status tool with no parameters and no output schema, the description covers the key dimensions an agent needs: it tells what state is inspected (busy, file, operation) and implies it is a safe, non-mutating query. It does not describe return format or error behavior, but given the tool's simplicity and the annotations covering read-only/open-world semantics, it is sufficiently complete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.