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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds valuable context beyond that: the per-note hours are data held by ScentVerdict rather than a general impression, and they are estimates. This caveat helps the agent set expectations about data provenance and reliability.

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?

Three sentences, each earning its place: the first defines the tool's behavior, the second gives usage triggers, and the third both qualifies the data and redirects to an alternative. There is no fluff or redundancy, and the most important information is front-loaded.

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?

Given a single parameter, a clear output schema, and comprehensive annotations, the description covers all needed behavioral caveats (estimates, data source) and usage routing. The agent can invoke the tool correctly without further clarification. Nothing essential is missing.

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 100%, and the only parameter, slug, is already documented with 'Use search_fragrances if you do not have one.' The description does not add parameter detail beyond the schema, so the baseline of 3 applies. There is no gap for the description to compensate for.

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?

The description states a specific verb and resource: 'Get how a fragrance develops over the wear: opening, heart and base phases, the notes in each, and how many hours each note persists on skin.' It clearly differentiates from get_fragrance by naming what that sibling covers instead. This leaves no ambiguity about the tool's scope.

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?

Explicit when-to-use guidance is given: 'Use this when the user asks how something evolves, how long it lasts, how it changes through the day, or what the drydown is like.' It also provides an explicit alternative: 'Use get_fragrance instead for the verdict, price and general description.' This fully covers routing between siblings.

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