Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden. It states a read-like action (list) but does not disclose whether it requires any setup, the scope of the list (e.g., all sources), or potential errors. It adds minimal behavioral context beyond the verb 'list', though the read-only nature 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.