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

Beyond annotations that already state readOnlyHint, idempotentHint, and destructiveHint, the description discloses the paid nature of the tool ($0.01/call via x402) and the 402 response with payment instructions when unpaid. It also reveals the return object structure, adding significant behavioral context that annotations do not cover.

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 well-structured: it starts with the core purpose, adds a usage note, then payment details, and ends with the return shape. Each sentence carries distinct value with no redundancy or filler.

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?

Even without an output schema, the description lists the exact return fields. It also covers payment behavior and error responses. Given the tool's complexity, this is fully sufficient for an agent to select and invoke it correctly, and the context distinguishes it from the many sibling shipping tools.

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?

The input schema has 100% parameter description coverage, with each parameter (country, limit, x_payment) already explained. The description adds no additional parameter-level semantics beyond what the schema provides, 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 uses the specific verb 'Get' and clearly identifies the resource as 'recent shipping regulatory updates and compliance requirements' scoped to a specific country. It distinguishes itself from sibling tools like 'shippingrates_rates' and 'shippingrates_congestion' by focusing on customs regulations, documentation, trade restrictions, and policy 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?

It provides a clear use case: 'Use this to stay current on regulatory changes that may affect shipments to/from a country.' However, it does not explicitly mention alternative tools or when NOT to use this tool, so it stops short of full exclusionary guidance.

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