Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple one-parameter tool, the description is minimally adequate, but it lacks details about the return type or behavior (e.g., whether it returns an array, whether hidden events are included). No output schema exists, so the description should explicitly mention the shape of the result. Sibling tools provide some context, but the description itself is incomplete.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.