Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description must carry the full burden of behavioral disclosure. It states the action and the return message but does not disclose potential side effects (e.g., overriding existing textures, modifying object materials), any permission requirements, or reversibility. The user_prompt instruction is about agent behavior, not the tool's own behavior, so it does not improve transparency.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.