Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly=true, idempotent=true, openWorld=true, destructive=false, so the safety profile is covered. The description adds a meaningful behavioral cue — that time-correctness rules should be consulted before backtesting and that the output supports cross-table reasoning — but does not disclose cost, latency, caching, or what happens with an invalid dataset_id.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.