store_create_shipping_zone

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

The annotations already indicate this is a create operation (readOnlyHint false, openWorldHint true, idempotentHint false, destructiveHint false). The description adds no additional behavioral details beyond what annotations provide—it does not mention requirements like the altId default, potential duplicate behavior, or any operational consequences. With annotations present, the bar is lower, but the description still fails to provide any supplementary context, earning a minimal score.

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 extremely concise—just four words—and contains no unnecessary words. It is front-loaded per se, but there is no structure beyond a single phrase. It avoids verbosity and is efficient for an agent to parse, though it misses the opportunity to provide useful context. A concise but complete description would be ideal, so this does not earn a 5 due to lack of content.

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 create tool with required fields and no output schema, this description is inadequate. It does not explain the business meaning of a shipping zone, the expected format of the 'countries' array, or any side effects or prerequisites. The schema provides some field descriptions, but the overall tool context is missing. An agent would struggle to understand when and how to use this tool correctly without additional documentation.

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 provides complete descriptions for all four parameters (name, altId, altType, countries) with 100% coverage. The description adds no information about parameters, but per the baseline rule, when schema coverage is high, a score of 3 is appropriate even without additional parameter details in the description. The description neither helps nor hurts parameter understanding.

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 'Create Shipping Zone' states a specific verb and resource, but it is extremely terse. It does not differentiate from sibling tools like store_create_shipping_carrier or store_create_shipping_rate in any way; the only distinction comes from the name itself. It is not vague, but it lacks any additional specification of what a shipping zone is or what it entails, so it barely meets the 'specific verb+resource' bar without added clarity.

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 context about prerequisites, side effects, or typical scenarios. It does not say when to use store_create_shipping_zone instead of store_update_shipping_zone or store_create_shipping_rate. There is no misleading information, but also no useful usage direction.

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