Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given no parameters, no annotations, and no output schema, the description covers the core behavior: it lists all levels and their elevations, sorted. It could possibly mention the output structure (e.g., array of objects), but for a straightforward tool, this is reasonably complete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.