Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, openWorldHint=false, and destructiveHint=false. The description adds valuable behavioral context: workspace token returns every website, website key returns only its own, and omitting both identifiers fails with a specific error. However, it also says 'Takes no parameters,' which inaccurately describes the tool's behavior relative to the schema.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.