Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a no-parameter read-only tool without an output schema, the description covers the essential aspects: what it retrieves, the authorization prerequisite, and the convenience factor. It doesn't enumerate possible statuses or explain 'hearted' further, but these are not blockers for making the call. It is adequately complete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.