get_country_info

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

With no annotations, the description must fully disclose behavior. It states the tool returns ISO-2/ISO-3 codes, name, continent, and currency, which is helpful. However, it does not clarify what happens when both parameters are omitted (e.g., returns all countries?), nor does it address edge cases or errors. The description also introduces ambiguity by saying 'resolve a country NAME' while the schema only has a 'code' parameter for ISO-2 codes, potentially misleading about input.

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 at two sentences plus a use case. It is front-loaded with a clear trigger statement. However, the slight contradiction between 'name' and 'code' introduces unnecessary noise. Overall, it is efficient but not perfectly clear.

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?

Given the tool's simplicity (2 optional params, no output schema), the description covers the main purpose and return fields. However, it fails to address the input ambiguity (name vs. code) and does not specify behavior when both parameters are missing. While the return format is described, the lack of clarity on inputs reduces completeness.

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 schema provides 100% coverage for both parameters ('code' and '_fields'). The description adds confusion by stating the tool resolves a country NAME, but the 'code' parameter is an ISO-2 code, not a name. This mismatch misleads about valid inputs. The description reiterates return fields but does not clarify the ambiguity or add meaningful detail beyond the schema.

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 purpose: to resolve a country name to its ISO-2 code for filtering airlines/airports. It specifies the resource (countries database) and the verb (look up). It also distinguishes itself from sibling tools by emphasizing its role as a helper for filtering, not for general facts.

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 instructs when to use the tool ('TRIGGER: use mainly as a helper to resolve a country NAME to its ISO-2 code for filtering airlines/airports') and when not to use it ('not for general country facts'). It provides concrete use cases, such as determining country codes for Bulgaria or Spain, and explains how it assists with filtering by country_code.

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