Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond annotations that already declare read-only/idempotent/non-destructive, the description adds substantive behavioral context: matches are deterministic, and the response includes evidence, caveats, and blocked lifecycle states. It also clarifies what the tool does not do (outreach, conversion, import, AI ranking), giving the agent a realistic expectation of the tool's boundaries.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.