Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of disclosure. 'Preview' implies read-only behavior and 'first N cells' clarifies the operational scope, but it does not explicitly state side effects, authentication needs, or what the returned preview contains.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.