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

Annotations already cover read-only, idempotent and non-destructive behavior, so the description's added value is the disclosure of return semantics: availability states (in_stock/out_of_stock/preorder), the preorder date, and that country drives language, prices and links. It does not mention failure behavior for an invalid sku, but the behavioral profile is otherwise well disclosed.

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 sentences, front-loaded with the resource and its returned fields, followed by the identification rule. The long field enumeration is dense but every item earns its place by substituting for the absent output schema.

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?

With no output schema, the description compensates by enumerating the returned fields and explaining availability and preorder semantics, and it covers both the identifier and the country parameter. An agent has everything needed to call it correctly.

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 description coverage is 100%, so both parameters are already documented; the description mainly restates that sku is the search_games field or a ficha URL and that country sets language/prices/links. It adds a useful cross-tool link but no syntax or format detail beyond the schema, matching the baseline 3.

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+resource ('Ficha completa de un juego de Zacatrus') and enumerates the exact fields returned (precio, disponibilidad, jugadores, edad, duración, temáticas, autores, editorial). An agent can distinguish it from search_games, which only lists games and yields the sku this tool consumes.

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: 'Identifícalo con el sku que devuelve search_games, o con la URL de la ficha', which establishes the search_games -> get_game workflow and the two accepted identifiers. It gives no explicit when-not or alternative-lookup guidance (e.g. store_stock for per-store availability), so it falls short of a 5.

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