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

Annotations already declare readOnly/idempotent/non-destructive/false openWorld, so the safety profile is covered. The description adds genuinely useful context beyond them: what is returned (id, título, enlace) and the intended search-then-fetch workflow. No limits or pagination are mentioned, keeping it below a 5.

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 tightly packed sentences: purpose first, then return contract, then workflow and alternative. No filler and nothing duplicated from the 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 sensibly documents the return fields, and the annotations carry the safety profile while the schema fully covers both params. Only minor gaps (result limits, pagination) remain.

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%: both 'query' (natural-language, with examples) and 'country' (enum es/fr with effect on language, prices, links) are fully documented in the schema. The description adds no parameter syntax or format detail beyond that, so the baseline 3 applies.

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 ('Búsqueda de texto libre en el catálogo de Zacatrus (juegos de mesa)') and precisely distinguishes itself from the sibling search_games by noting it is the no-filter equivalent. It also names the concrete return fields (id, título, enlace), so an agent knows exactly what it produces.

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 names the alternative (search_games), explains the relationship ('sin filtros'), and gives the intended audience ('clientes que solo conocen search y fetch'), plus a follow-up step ('usa fetch con el id'). It stops short of an explicit exclusion rule ('use search_games when you need filters'), which is only implied.

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