Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple tool with one parameter, no output schema, and annotations covering destructiveness and idempotency, the description adequately covers purpose, when to use, and parameter. It does not explain behavior on missing keys, but the idempotent hint implies no error. Overall sufficient for the tool's complexity.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.