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

The description adds cost and premium API info, but it states 'Retrieve', implying a read-only operation, while annotations set destructiveHint=true. This contradiction reduces transparency. No additional behavioral details (e.g., side effects, rate limits) are provided.

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 composed of two concise sentences. The first sentence lists all relevant data points in a clear structure, and the second adds cost information. There is no wasted text.

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?

The description lists the types of rates and restrictions returned, which is helpful given the lack of an output schema. However, it does not mention the format or potential errors, leaving minor gaps. Overall, it provides sufficient context for a premium API tool.

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%; both parameters have descriptions in the input schema. The description does not add further semantics beyond what is already in the schema, so the baseline score 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 clearly states the tool retrieves import customs duty rates for any HS code and destination country, listing specific rate types (MFN, FTA, VAT/GST, etc.). It uses a specific verb 'Retrieve' and resource 'customs duty rates', effectively distinguishing it from sibling tools that handle addresses, companies, etc.

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 explicitly states when to use the tool: to retrieve customs duty rates for any HS code and country. It provides context but does not discuss when not to use or alternative tools. However, the specificity of the tool's function makes its usage clear.

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