Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The readOnlyHint=true annotation already tells the agent this is a safe, non-mutating read. The description adds value by naming the categories of data returned (phases, deliverables, expenses, transactions), but says nothing about authorization needs, missing-project behavior, or response shape beyond that list.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.