Estimate Brazilian import tax & landed price (free)

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

With no annotations provided, the description bears the full burden of behavioral disclosure. It transparently states that the tool is free and deterministic, explains the calculation rule (0% up to US$50, else 30% − US$20), notes the ruleset version and potential changes, clarifies it's an estimate with the marketplace as source of truth, and explicitly says 'No payment.' This goes beyond typical descriptions.

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 concise and efficiently structured. It front-loads key attributes ('FREE, deterministic'), then explains inputs, outputs, and caveats in a few sentences. Every sentence adds essential information without 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?

Given the tool's complexity (7 parameters, no output schema, no annotations), the description is remarkably complete. It specifies the return values (Import Tax, ICMS, total landed price, USD rate, ruleset version), the input alternatives, the legal basis, and the estimate's limitations. This fully compensates for the lack of structured metadata.

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 baseline is 3. The description adds meaningful context by clarifying the exclusive grouping of BRL cents vs USD fields and specifically names product_cents/freight_cents and product_usd/freight_usd, complementing the schema descriptions. It also highlights the optional 'uf' state. This adds value beyond the schema.

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 clearly states the tool's function: it estimates Brazilian import tax and final landed price for cross-border purchases. The verb 'estimates' is specific, and the resource (import tax/landed price) is clearly identified, distinguishing it from the sibling search tools.

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 provides clear usage context: it explains when to use the tool (for estimating import tax/landed price), how to provide inputs (BRL cents or USD, not both, optional state), and what outputs to expect. It does not explicitly mention alternatives because none are relevant (siblings are search tools), but it gives no misleading exclusions.

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