Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It labels the operation as 'READ', which implies non-mutating behavior, but says nothing about return format, error conditions, or whether the schedule is for a specific date range. The word 'READ' is largely redundant with the 'get' in the tool name.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.