Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. 'Display metadata' usefully signals that geometry is unaffected, but it omits everything else an agent needs: whether the change is persistent, whether it requires an undo checkpoint or transaction, what valid lineweight values or units are accepted (e.g. ByLayer/ByBlock sentinels), and what happens on invalid input.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.