Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a tool with ten parameters and a write side effect, the description covers the essential context: when to use it, what it writes, where it writes, and how to avoid affecting the public feed. An output schema is listed as present, which reduces the need to describe return values.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.