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

With no annotations, the description carries the full behavioral burden, and it delivers: it says the tool is 'queried live at call time from rulings.cbp.gov' and 'nothing is mirrored here,' clarifying freshness and provenance. It also discloses that rulings may be revoked or modified and that chapter 99 headings carry Section 301 additions, which materially affects interpretation.

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?

The description is compact, front-loaded with the primary action, and every sentence adds value: what it searches, what it returns, why it matters, and how the data is sourced. There is no filler or repetition.

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?

There is no output schema, so the description must explain return values, and it does: ruling number, date, subject, assigned HTS codes including chapter 99, and revocation/modification status. Combined with the live-source note and usage context, an agent has enough information to invoke the tool and interpret the result.

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?

Both parameters already have detailed schema descriptions: query is described as an ordinary-word product and limit has range and default. The description reinforces 'plain words' and mentions comparable goods, but it adds little beyond the schema, so the baseline of 3 is appropriate.

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 names a specific verb and resource: 'Search CBP's own binding classification rulings (CROSS)' for a product in plain words. It also enumerates what the call returns, making it clearly distinct from sibling tools that handle import claims, duty stacking, or rule changes.

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?

The description gives an explicit use case: checking whether a supplier-provided HTS code matches what CBP has ruled on comparable goods. It does not explicitly name sibling tools or state when not to use it, but the 'not a guess' framing and reference to Section 301 additions make the intended context strong.

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