Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden and does a genuinely good job on the cost dimension, disclosing that it costs $0.50 USDC via x402 and is charged only on success. It also discloses that metrics are computed automatically. It omits other behavioral traits like idempotency, partial-failure handling, and the 300-asset cap, which keeps it out of the top band.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.