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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the description does not need to repeat those. However, the description adds minimal behavioral context: it indicates the subject type (company or person) and UBO concept, but does not disclose any details about the return format, privacy, or data completeness. It neither contradicts nor richly supplements annotations.

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 description is a single, short sentence, which is concise and front-loaded. It contains no fluff. However, it is almost too brief, lacking key details, but for what it does include, it is well-structured.

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?

Given there is no output schema and the tool involves 3 parameters with no descriptions, the description is incomplete. It does not mention required inputs (although none are required), how the 'completo' flag affects the response, or any edge cases. The tool is likely part of a larger investigation suite, but without more guidance, agents may misuse parameters.

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?

With 0% schema description coverage and no parameter descriptions in the schema itself, the description carries the burden of explaining parameters. It does not explain what CPF, CNPJ, or completo mean or how they are used. The parameter names are self-explanatory to some extent, but the description adds no semantics beyond the schema names, which is insufficient.

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?

The description 'Beneficiário final (UBO) de uma empresa ou pessoa' expresses the resource (UBO) and that it relates to a company or person, but it does not state the action (e.g., 'consulta', 'obter', 'investiga'). It is clear in conjunction with the name, but does not distinguish from sibling investigation tools, many of which relate to people or companies.

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?

The description implies this tool is for obtaining UBO information about a company or person, but it does not explicitly state when to use it over sibling tools like investigacao_pessoa_fisica or investigacao_pessoa_juridica, nor does it provide any exclusion criteria. It is sufficient for a basic understanding but lacks explicit guidance.

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