Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden but discloses almost nothing: it does not explain that `ref` comes from a prior snapshot, whether the field must be focused first, or what the `submit` flag triggers (e.g. form submission/navigation). Only the bare mutation intent is implied.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.