goat_countries

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

No annotations are provided, so the description must carry the full burden. It discloses that the data is credential-free public data and that it returns every country, not just shippable ones, clarifying a potentially surprising behavior. It does not mention rate limits, pagination, or response structure, but for a simple read-only list tool, these are minor omissions. The description adds value beyond the minimal schema.

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 (about three sentences) and front-loaded with the core purpose. Each sentence adds necessary detail: what it returns, why it lists all countries, and how to filter for shipping. No filler or redundant information.

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 tool with no parameters and no output schema, the description is quite complete. It enumerates the fields (currency, size unit, ships_to, returns) and explains the rationale for including all countries. It lacks explicit mention of response format (e.g., field names) but that can be inferred. It also omits potential limitations like data freshness, but overall it provides sufficient context for an agent to invoke it correctly.

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?

There are zero parameters, so the baseline is 4. The description correctly notes that there are no parameters (implicitly by having no mention) and explains the output content. Since there is nothing to add beyond the schema (which is empty), the description adequately covers parameter 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?

States a specific verb and resource: 'Get GOAT countries.' Clearly defines the resource as the list of countries GOAT recognizes, with details on what attributes are returned (currency, size unit, shipping/returns). Distinguishes from other GOAT tools by being a reference list for the country_code parameter. The purpose is unambiguous and specific.

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?

Provides context on when to use this tool: to get accepted country_code values for GOAT product endpoints. Mentions filtering on 'ships_to' for shipping destinations, implying use cases. However, it does not explicitly name alternative tools or state when not to use it, but given the uniqueness of this resource, the guidance is sufficient.

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