Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations (readOnlyHint, idempotentHint, destructiveHint) already declare a safe read operation. The description adds only the return type (DataFrame) and data content, but no additional behavioral context such as data frequency, coverage, or potential side effects. With annotations present, this is an average contribution.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.