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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds the auth requirement ("conta ou convidado"), genuine context beyond annotations, but says nothing about result limits or matching behavior.

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?

A single front-loaded sentence carrying purpose, search keys and access precondition with zero filler. Nothing could be trimmed without losing 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?

For a one-parameter read-only search with no output schema, the description covers purpose, accepted keys and the auth requirement. Slightly short of perfect because it omits match semantics (exact vs partial) that a search tool's caller might want.

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% and the single parameter q is fully documented in the schema (CNPJ completo ou nome de 3 a 120 caracteres). The description restates the accepted key types but adds no syntax or normalization detail beyond what the schema already provides, so baseline 3 is correct.

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 ("Busca") and resource ("base cadastral") and names the two search keys (CNPJ or razão social). Clear enough to act on, but it does not distinguish itself from siblings such as minhas_empresas or buscar_licitacao.

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?

"exige conta ou convidado" gives a useful access precondition, which implies when the tool is callable. However, there is no guidance on when to prefer this over adjacent tools (e.g., selecionar_empresa, adicionar_empresa), so usage is only implied.

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