Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden. 'Get' implies a safe read, but it says nothing about ordering, pagination, whether inactive stages are included, or what happens with an invalid pipelineId. For a zero-annotation tool this is a meaningful gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.