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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds genuinely useful context beyond that: the approximate response size (~12 KB) and the presence of a count and an attribution line, which helps an agent plan for payload handling.

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?

Three short sentences, front-loaded with what is returned, then the response format, then the alternative. Nothing is redundant and every sentence carries information an agent would act on.

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?

There is no output schema, so describing the returned fields, size, and shape is exactly the right compensation and it is done well. The only gap is that the description says nothing about how the locale parameter changes the response, though the schema handles that.

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 single locale enum is fully documented in the schema, so baseline is 3. The description adds no meaning about locale or its effect on the returned prose, leaving that entirely to 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 names a specific resource and its exact payload: every country with ISO code, slug, document count, and page URL. It also distinguishes itself from the sibling find_document, so an agent can tell the two apart without opening either schema.

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?

It gives an explicit routing rule: use find_document when the user already named a country, which implies this is the enumeration/browse tool. It does not cover other conditions such as pagination limits or whether locale matters for selection, but the key alternative is named with its trigger.

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