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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds value beyond that by disclosing what comes back (codes, rates, Section 301 China status), which is important since there is no output schema. It does not mention result-count behavior or ranking semantics.

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?

Front-loads the trigger before the mechanics, and the parenthetical example phrasings earn their place by improving matchability. Slightly longer than strictly needed, but every sentence carries routing or output 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?

For a two-parameter search tool with no output schema, the description covers the trigger, the returned fields, and the hand-off to the sibling. The only real gap is the undocumented limit parameter and any note on result ordering.

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?

Only the query parameter is documented, and that documentation lives in the schema, not the description. The limit parameter (default 8, max 20) is undocumented in both places, leaving half of the parameters unexplained; the description compensates with nothing.

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 (searches) and resource (official US Harmonized Tariff Schedule) and describes the output (best matching codes with rates and Section 301 China status). It is clearly distinguishable from the sibling lookup_hts, which it explicitly routes to for single-code detail.

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?

Opens with an explicit trigger ('Use this when the user describes a product and wants its US HTS code...') and supplies representative user phrasings. It also names the alternative tool and the condition for switching to it ('Then use lookup_hts for full detail on one code').

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