Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a mathematical operation tool with no annotations, no output schema, and 0% schema description coverage, the description is incomplete. It doesn't address what happens with non-numeric inputs, rectangular vs square matrices, error conditions, or the format of the return value. The context demands more information than provided.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.