Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint=true and openWorldHint=true, covering the safety profile. The description adds only the word 'recorded', implying retrieval of pre-existing data, but does not describe return format, error behavior (e.g., missing weather), authentication needs, or rate limits. It adds minimal value 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.