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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds useful context that results are 'normalized' and that the storefront URL is fixed, telling the agent it need not construct a full URL. It does not add auth or rate-limit detail, but that is minor for a read tool.

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: purpose first, then alternative routing. Every clause earns its place with no redundancy.

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?

Purpose, input, and sibling routing are all present; return values are covered by the existing output schema and safety by annotations. Nothing an agent needs to invoke this correctly 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 coverage is 100% and the handle param is already documented as a URL slug. The description adds meaning beyond the schema by clarifying that only the handle is needed because 'the storefront URL is fixed', removing ambiguity about full-URL input.

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 (Fetch) and resource (normalized product details for one Kylie Cosmetics product), and identifies the input (URL handle). It also names the sibling tools it is not, so an agent can distinguish it without opening another schema.

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?

Explicitly routes the agent: kyliecosmetics_products to browse the catalog, kyliecosmetics_search_suggest for typeahead, and kyliecosmetics_product_recommendations for related items. The when-to-use-this vs. alternatives is fully spelled out.

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