Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple one-parameter destructive tool, the description is adequate: it names the target, defines the consequence, and warns about irreversibility. It could mention what happens when the inbox does not exist or whether this is the only way to permanently destroy an inbox, but nothing essential is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.