Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple polling tool with an output schema, the description is complete. It covers purpose, usage context, both parameters, and return semantics including error handling. The presence of an output schema means exhaustive return details are not necessary, and the description fills all critical gaps.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.