Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It discloses the placement behavior (after original) and that it returns the new index. However, it does not mention any side effects, required permissions, or error handling (e.g., what happens if slide_index is out of bounds). The transparency is adequate but not rich.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.