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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds extra context beyond annotations: 'não é dado sigiloso' and LGPD note about data controller responsibility, which informs safety and legal handling. No contradiction with 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 concise, a single paragraph that front-loads the core purpose. It includes necessary operational details (payment, no credentials) and a legal note (LGPD), which adds length but is relevant context. There is minimal fluff, earning a high score.

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 no output schema, no parameter descriptions, and low complexity (3 simple string params), the description is incomplete. It does not specify what identifiers are valid (e.g., IE, CPF, CNPJ format) or what the response contains. The description only states the query purpose but leaves the agent without input guidance or expected output details.

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 has 3 parameters (ie, cpf, cnpj) with no descriptions, and schema coverage is 0%. The description does not mention any of these parameters, nor their purpose (e.g., which to use for which entity type). It fails to compensate for the lack of schema guidance, leaving the agent unclear on how to populate the inputs.

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 explicitly states 'SEFAZ PA: Certidão Negativa de Débitos, consulta em fonte oficial' — a specific verb (consulta) and resource (Certidão Negativa de Débitos) with a clear reference to official Brazilian sources. It is unambiguous and distinct from sibling tools (authenticate, connect, etc.), which are unrelated.

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 provides context on when to use: 'consulta em fonte oficial' and 'Hospedado pela plataforma, sem credenciais da plataforma, pague por consulta com crédito pré-pago' — clarifying that it's a paid, credential-free query. However, it doesn't explicitly contrast with alternatives or state when not to use it, though no direct alternatives exist among siblings.

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