Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given an output schema exists, all parameters are documented with 100% schema coverage, and annotations cover safety traits, the description completes the picture: it explains the product context, level semantics, hazard coverage, and how to handle other risk-zone products. Nothing essential is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.