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

Annotations already establish readOnlyHint=true and destructiveHint=false; the description adds useful context about prepaid credits, official sources, non-confidential data, and LGPD responsibility. However, the claim 'sem credenciais' conflicts with the presence of credential parameters (login_cpf, login_senha, pkcs12_cert, pkcs12_pass), creating ambiguity about the actual authentication requirements.

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 front-loaded with the core purpose, then adds concise operational context. It is one short paragraph with no filler, though the LGPD sentence is somewhat boilerplate and could be trimmed without losing essential tool usage 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?

Despite the clear purpose statement, this tool has 8 parameters, no required fields, and no output schema. The description does not explain the return format beyond 'NIRE', and it fails to document most parameters, particularly authentication-related ones, making it insufficient for an agent to reliably invoke the tool with the correct inputs.

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 0%, so the description must compensate for parameter meaning. It clarifies socio_nome, socio_cpf, and socio_cnpj, but leaves login_cpf, login_senha, pkcs12_cert, pkcs12_pass, and inclui_inativas unexplained, with the 'sem credenciais' statement further muddying the credential fields.

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 opens with a specific verb and resource: 'Encontra empresas na JUCESP a partir de um sócio (nome, CPF ou CNPJ), retornando o NIRE de cada participação.' It clearly states what the tool does and the output (NIRE), and it is distinct from the unrelated sibling tools.

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 provides clear context about when this tool is appropriate: it is a hosted, credential-free, pay-per-query lookup of official Brazilian data. It does not explicitly name alternative tools or when-not-to-use scenarios, but no sibling appears to be a similar data lookup, so the context is sufficient.

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