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

Annotations already cover the safety profile (readOnlyHint, openWorldHint), yet the description adds that each suggestion carries its own live total result count and that this is not product data. That is meaningful behavioral context about the response shape beyond the annotations, though nothing about rate limits or ranking is disclosed.

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 what the tool returns and the site selector, ending with the disambiguating 'Not product data' note. No filler; every clause adds information.

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?

With an output schema present, return values need no explanation, and the description covers purpose, scope, input default, and the response nature. The only gap is explicit when-to-use routing versus jcrew_search, which a sibling-differentiation sentence would close.

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%, so both params are already documented, but the description adds a detail the schema lacks: the default value 'jcrew' for site. It also reinforces that query is partial. This goes slightly beyond the structured fields.

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: search-box typeahead suggestions for a partial query, with per-phrase live result counts. It also scopes the tool ('Not product data' and 'select with site'), which separates it from jcrew_product and jcrew_search without the agent 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?

Implies usage through 'search-box suggestions (typeahead)' and gives input scoping ('select with site, default jcrew'), but never states when to prefer this over jcrew_search or how partial the query should be. Usage is inferable rather than explicit.

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