Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so safety needs no restating. The description contributes nothing about what the retrieved markdown contains, its format, or how it differs from the CSV/XLSX export siblings, and its 'export mixin' framing actively mischaracterizes the output.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.