Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It does disclose meaningful behavior by pairing 'Replace' with HTTP PUT, which signals full-resource replacement rather than partial update. However it says nothing about what the replacement body must contain, auth needs, or reversibility of the overwrite.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.