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

With no annotations, the description carries full behavioral burden but does reveal useful traits: a fixed, complete set of 90 entries and the ISO-code-prefix format. It does not mention whether results are cached, rate-limited, or paginated, and gives no safety or auth context.

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?

One tight sentence that front-loads the action, resource, cardinality, and payload meaning with no filler.

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 zero-param, read-only listing with no output schema, the description covers what the tool is, the size of the result set, and the meaning of each entry. It is nearly complete; only return-format details (e.g., plain list vs. ISO-to-name mapping) are left unspecified.

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?

Zero parameters, so the baseline is 4. The description usefully clarifies that returned ISO codes function as spec prefixes, adding semantic value even though no parameters exist to document.

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 (List) and resource (countries) plus the exact scope (90 countries for synthetic test data) and the practical value of each entry (ISO code as spec prefix). Issues like this make it immediately distinguishable from siblings such as sampuli_describe_country, which is a per-country lookup rather than a full listing.

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 implies usage (enumerating available countries before generating data) but never states when to call this versus sampuli_describe_country or sampuli_generate, nor any prerequisites. Context is inferable but not explicit.

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