Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It states 'List all' but fails to mention that pagination via limit/offset constrains the result set, which could mislead an agent into expecting every creative in one response. It also omits details about read-only guarantees, response format, or potential filtering, making the behavior partially opaque.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.