Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds a meaningful behavioral trait beyond the annotations — tier-gated output where free users see only total check-ins and Pro sees full breakdowns — which the agent cannot learn from structured fields.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tight sentences, front-loaded with what the tool aggregates, and the tier caveat plus sibling routing is packed without waste. Nothing here is filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only statistics tool with no output schema, the description covers purpose, tier limitations and alternatives adequately. Minor residual gaps are the lack of any parameter guidance and the unaddressed distinction from user_get_wearing_history.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 67%, and the description mentions no parameters at all — not the fragrance UUID, the required context string, nor response_format. It neither adds syntax nor compensates for the uncovered third of the schema, so it sits at the baseline rather than above it.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Aggregate wearing statistics for a fragrance') and enumerates the dimensions returned — when worn, seasons, mood tags. It also names the sibling tools it is not (fragrance_get, fragrance_similar), so an agent can separate it from the profile and alternatives tools.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The 'See also' line explicitly routes to fragrance_get for full profiles and fragrance_similar for alternatives with similar profiles, giving clear context for selection. It does not, however, address the adjacent sibling user_get_wearing_history, leaving a small ambiguity about whose wearing data this covers.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.