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

The description adds critical behavioral context beyond the annotations: a payment requirement ($0.01/call via x402), the 402 response without payment, and the full return object structure. This is essential for the agent to invoke the tool correctly and handle failures, and it does not contradict the read-only/idempotent hints.

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 tightly written: a concise purpose statement, a one-sentence usage guideline, and a terse payment/return specification. Every sentence adds distinct value, and the structure is logical and front-loaded.

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 read-only data tool with no output schema, the description provides the return structure, payment requirement, and error behavior, covering the essential operational details. Minor omissions like case-sensitivity of country codes do not significantly impact usability.

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?

All three parameters are fully documented in the input schema (country code format, limit range/default, x_payment header). The description does not add further parameter details, but given 100% schema coverage, the baseline 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's function with a specific verb ('Get'), resource ('recent shipping regulatory updates and compliance requirements'), and scope ('for a specific country'). It also lists concrete content areas (customs, documentation, trade restrictions) and is easily distinguished from sibling tools, none of which focus on regulatory updates.

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 says 'Use this to stay current on regulatory changes that may affect shipments to/from a country,' providing a clear use case. It does not mention alternatives, but the tool is unique among siblings, so explicit exclusions are unnecessary.

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