Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true. The description adds the explicit 'Read-only' label, which is consistent but redundant. It doesn't describe the actual response shape, data freshness, or any caveats about the status surface. Since annotations cover the safety profile well, the description provides minimal additional behavioral context, so a 3 is appropriate.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.