Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden. It warns that mode='overwrite' replaces existing target programming, which is a key behavioral trait. However, it does not disclose other side effects, permissions needed, or whether the operation is reversible. The return value is mentioned as a string but not detailed.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.