Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a multi-step research tool, the description covers the essential behavior (3 searches, AI-written brief, citations, cost). An output schema exists to define the return format, so the description doesn't need to. It lacks only explicit guidance on usage scenarios, but is otherwise complete for its complexity.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.