Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds substantial behavioral detail beyond the annotations: it specifies that only the latest version is considered, enumerates returned fields, explains the conditional availability of column names for TABULAR-INGESTED files, and explicitly states that the response will say column names are unavailable rather than silently omitting them. This is rich, accurate context that helps an agent predict behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.