Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral context beyond that: liquidity-sorted output, pricing ($0.02/call), x402 transport on Base, the optional prepaid x-credit-token header, one free call/day, and no wallet/API key requirement. There is no contradiction with the annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.