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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful behavior beyond that — page-based pagination and combinable facets — but says nothing about rate limits, result caps, or how facets interact with the keyword, so the added context is modest rather than rich.

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 sentences, front-loaded with the capability summary and then the sibling routing. No filler, no repetition of the parameter names beyond what routing requires.

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?

An output schema exists, so return values need no explanation, and the schema fully documents all ten inputs. The description covers scope, routing, and pagination behavior — everything an agent needs to invoke it correctly.

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 schema already documents every parameter in detail, including the price_min/price_max pairing caveat and the facet value list. The description only recaps the same parameter set (keyword, sort, price range, brand, rating, newness, facets), adding no syntax or format detail beyond the schema, so baseline 3 applies.

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?

State a specific verb (Search) and resource (Sephora products) plus the full capability set: keyword, sort, price range, brand, rating, newness, facets, and pagination. It also names the sibling tools it is not (sephora_suggest, sephora_category, sephora_product), so an agent can distinguish it without opening any 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 to the correct alternative: typeahead → sephora_suggest, browse listings → sephora_category, single item → sephora_product. That is clear when-to-use guidance for alternatives, though it never states a negative condition for this tool itself (e.g. when a full search is overkill).

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