Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of disclosing behavior. It states the tool 'returns' data, implying a read-only operation, and mentions the data source. However, it does not explicitly state that it has no side effects, nor does it describe error scenarios or authorization requirements.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.