Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. 'Find' implies a read operation, but there is no mention of return format, ordering, pagination, or any side effects. The description adds only the fact that haikus are 3-line poems, which clarifies semantics but not behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.