Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true and openWorldHint=false, so the safety profile is covered by structured data. The description adds semantic context about what open questions represent, but says nothing about the lifecycle nuance (the schema notes 'open' questions may be replaced on regeneration), which would be the valuable extra detail.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.