Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the burden of behavioral disclosure. It explains how non-point features are treated ('Non-point features use their centroid'), the minimum input requirement, and the return structure ('Returns JSON {ok, cell_count, geojson}'). This goes beyond the schema, but lacks details on error conditions or coordinate system handling.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.