Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden but only states it's a read operation. It doesn't disclose behavioral traits like authentication needs, rate limits, return format (e.g., JSON structure, pagination), or error conditions. The phrase 'all VITAL metric samples' suggests comprehensive retrieval but lacks detail on scope constraints.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.