Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It discloses the read-only nature ('Fetch') and return format (Markdown with title, metadata, description, content). However, it does not mention error handling, exact-match failure behavior, authentication requirements, or any other behavioral traits beyond the basic fetch. Some transparency is provided, but gaps remain.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.