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

Annotations already declare readOnlyHint and openWorldHint; the description adds that the directory is 'public' (implying no auth needed) and scopes results to a single country. It does not mention pagination or result volume, but adds meaningful context beyond the structured hints.

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?

Two tight sentences: the resource and its contents first, the prerequisite second. No filler, and the alternative is front-loaded after the core purpose.

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 one-parameter read-only tool with an output schema and safety annotations, the description covers purpose, scope, and how to obtain a valid country code. Only minor gaps remain (invalid-country behavior, result size).

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 0%, so the description must carry the parameter meaning. It explains that the single 'country' param takes a country code and points to balenciaga_store_countries for discovering valid values, though it does not give the code format (e.g., ISO-2).

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 resource ('Balenciaga's public physical-store directory for one country') with a clear scope and enumerates what it returns (addresses, coordinates, phone, hours, service flags). It is immediately distinguishable from sibling balenciaga_store_countries and from product/search siblings.

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?

Explicitly routes the agent to balenciaga_store_countries for valid country codes, which is the key prerequisite for calling this tool. It does not spell out when-not to use it (e.g., vs a store-search tool), but the context is clear.

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