Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple read-only tool with annotated safety and 100% schema coverage, the description covers purpose, usage, and a key behavioral trait (snapshot comparison). However, with no output schema, it does not explicitly describe the return value; it only implies the output includes the detected changes. This is a minor gap, but the tool context is still sufficiently complete for selection and invocation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.