Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden for disclosing behavioral traits. It does not explain what happens to the duplicate's properties, naming, position, or whether it is a deep copy. It also does not state whether the tool returns the new layer's ID or modifies the scene state beyond duplicating. This is a significant gap for a mutation-style tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.