List VAT zones

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It indicates a 'fetch' operation (implying read-only), but does not mention authorization requirements, rate limits, response format, or any side effects. The description is too minimal to disclose behavioral traits beyond the basic action.

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 a single, concise sentence that front-loads the core action and resource. No wasted words or redundant information, and it appropriately avoids repeating schema details.

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 tool is simple with two well-documented parameters, but no output schema or annotations exist. The description covers the basic purpose and pagination, but leaves out any mention of the return value structure or whether it returns a list of VAT zones. It is minimally viable but lacks some context that would help the agent fully understand the tool's behavior.

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 fully describes both parameters (page and pageSize) with clear descriptions and defaults, so schema coverage is 100%. The description adds no extra parameter-specific meaning, but the baseline of 3 is appropriate since the schema already provides the necessary semantics.

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 action ('Fetch') and resource ('a page of VAT zones'), using a specific verb and resource that distinguishes it from sibling tools like list_customers or list_products. The pagination aspect is also explicitly mentioned, making the purpose unambiguous.

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 no guidance on when to use this tool versus alternatives, nor any exclusions or prerequisites. It simply states the function without contextual cues about use cases or comparisons to other list tools. No alternatives are mentioned.

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