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

The annotations already declare readOnlyHint, idempotentHint, non-destructive and openWorldHint=false, so the safety profile needs no restatement. The description does add useful behavioral context: the index spans guides, glossary entries, films, grape/region pages, indexes and tools, and matching is phrase-based. It says nothing about result ordering, limits or the shape of the response, which matters since there is no output schema.

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 scope is front-loaded in the first sentence, which is good. But the closing English sentence ("Site search over guides, glossary, films and pages") restates the Portuguese list nearly item for item, so a meaningful share of the text is redundant. The metaphor "A lupa da casa" is charming but costs tokens without adding selection signal.

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?

This is a simple two-parameter search with full schema coverage, complete annotations and no output schema, so most of the agent's needs are met elsewhere. What is left unresolved is the sibling overlap and the response shape (what a result looks like, how many come back). The phrase "Pra verbete, a descrição já é a resposta" hints at result structure but is too cryptic to substitute for that missing detail.

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%, with both 'frase' (max 200 chars) and the 'lingua' enum already documented in the schema, so the baseline is 3. The description's "pela frase" only echoes what the schema states. It adds no meaning about the interaction between query language and the 'lingua' parameter.

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?

"Acha ... pela frase" gives a specific verb (find/search) and enumerates the resource types covered: guias, verbetes do glossário, filmes, páginas de uva e de região, índices e ferramentas. That is far more specific than a tautology. It does not, however, explain how it differs from the overlapping siblings pagina_de_uva_ou_regiao, verbete and buscar_vinhos, all of which appear to return some of the same content types.

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?

There is no when-to-use or when-not-to-use guidance and no routing to the sibling tools. Because the description claims it finds uva/região pages and glossário verbetes, an agent cannot tell from this text why it would pick buscar_no_site over pagina_de_uva_ou_regiao or verbete. The line "Pra verbete, a descrição já é a resposta" gestures at behavior but is not expressed as a usage rule.

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