Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the entire behavioral burden and does not meet it: it never states that this is a write/create operation, whether duplicates are allowed, whether the caller is auto-assigned, or what happens if the workspace is omitted. Only the bare word "Add" hints at mutation, and nothing is said about side effects or permissions.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.