Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the readOnlyHint/idempotentHint annotations, the description adds meaningful context: it mentions the specific USDC amount, chain, the transition from pending to verified, and the inclusion of a txHash and Basescan link. This enriches the agent's understanding of the polling behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.