Resolve a country name to its ISO-2 code

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

No annotations are provided, so the description carries the full burden. It explains the transformation (to uppercase), input acceptance (name or existing code), and error behavior. For a simple lookup, this is adequate, though it could mention if it requires authentication or has rate limits.

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 two sentences, very concise, and front-loaded with the main purpose. Every sentence adds value, and there is no redundancy.

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 (one parameter, no output schema, no nested objects), the description is complete. It covers purpose, usage, input flexibility, example, and error handling.

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?

Schema coverage is 100% and the description adds value beyond the schema: it clarifies that the parameter can be a country name or an existing ISO-2 code, and provides an example. The schema only states 'A country name or ISO-2 code'; the description enriches 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 clearly states the tool's function: resolve a country name or existing ISO code to its uppercase ISO-2 code, with an example ('Kenya' → 'KE'). It also distinguishes itself from the sibling tool 'check_visa' by noting it's useful before calling that tool.

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 states when to use the tool ('useful before calling check_visa') and what happens on error ('returns an error if the name can't be resolved'). It does not explicitly state when not to use it, but the context is sufficiently clear.

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