Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is known. The description adds context beyond these by clarifying that on-chain execution is simulated rather than real, and by disclosing the price, payment mechanism (x402), and supported networks.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.