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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower, and the description still adds real behavioral context: the response maps an input id to ids on all other platforms, the id should match the store URL form, and up to 100 ids can be passed comma-separated in one call.

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 purpose and id-format guidance are well front-loaded, but enumerating all 23 source values duplicates the fuente enum already present in the schema and consumes most of the text without adding information.

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?

No output schema exists, so the description must explain the return, and it does ('devuelve sus ids en todas las demás') plus batching limits. Together with the enum for fuente, an agent has enough to invoke it correctly; only the explicit sibling routing is missing.

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 only 50%, so the description has to compensate, and it does: it explains that the input id is a store/database id valid as it appears in the URL, and that the id field accepts up to 100 comma-separated values. This meaningfully extends the schema's brief 'uno o varios ids separados por comas'.

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 and resource ('Encuentra la ficha de un juego a partir de su id... y devuelve sus ids en todas las demás') with a concrete example (Xbox id -> Steam appid). The purpose is unmistakable, though it never explicitly names how it differs from sibling tools like buscar_juegos or ficha_juego.

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 implies when the tool is useful (cross-referencing an external store id) and clarifies that the id should be given as it appears in the store URL. However, it gives no explicit guidance on when to prefer it over buscar_juegos or ficha_juego, so the routing decision is left to inference.

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