Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations indicate readOnlyHint=true and openWorldHint=true. The description adds that results are most recent first, large results are trimmed to fit context window, and blockchain-specific wallet type availability. This provides meaningful behavioral context beyond annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.