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

The annotations already establish that this is a read-only, idempotent, non-destructive, closed-world operation. The description adds useful behavioral context by specifying the categories of information returned, including data freshness and exclusions, though it does not discuss response shape or language-dependent behavior.

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 definition is a single, front-loaded sentence that enumerates the relevant content without waste. Every listed item contributes to understanding what the tool returns.

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 low complexity, complete parameter schema, existing output schema, and safety annotations, the description provides enough context for an agent to understand what the tool does and what information it returns. No critical missing detail would prevent correct invocation.

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 single optional 'lang' parameter is fully documented in the schema, including enum values, language meanings, and default behavior. The description mentions languages as part of the returned information but does not add meaning beyond the schema's own parameter documentation, so the baseline score of 3 is appropriate.

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 uses a specific verb, 'Describes,' and names the resource, Guía Extranjeros, while enumerating the exact information it returns: coverage, languages, guide counts, freshness, exclusions, and personal help. This clearly distinguishes it from the sibling tools get_guide and search_guides, which retrieve or search guides rather than describe the service.

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 when the tool is useful by listing the meta-information it provides, such as coverage and limitations, but it does not explicitly say when to use this tool instead of get_guide or search_guides. The usage context is inferable but not stated as a guideline.

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