Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden, but it does disclose a key behavioral trait: it returns bounded excerpts and 'the host composes the answer', meaning this tool does not synthesize a final answer. That is useful context, but the description omits return format, size-limit behavior, and other operational details.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.