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

Beyond annotations (readOnly, idempotent, non-destructive), the description adds meaningful behavioral details: it mentions prepaid credit cost, no platform credentials required, and LGPD compliance. This enhances transparency about side effects and data handling.

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 relatively short but contains redundancy (e.g., repeating 'consulta' and official source info). It could be more tightly structured, but it does not contain excessive verbosity.

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?

With no output schema, the description should provide context about expected results or return data. It mentions the source and legal aspects but does not clarify what the tool actually returns (e.g., certificate status, JSON structure). It also fails to elaborate on the parameters, leaving the tool's overall usage incomplete.

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?

The schema defines three parameters (ie, cpf, cnpj) with no descriptions, and the tool description does not explain what they stand for or their expected formats. The description adds no value to parameter understanding, and schema coverage is 0%.

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 clearly states the tool is for consulting a negative debt certificate (Certidão Negativa de Débitos) from an official source. It specifies the action (consulta) and resource, distinguishing it from the sibling tools like authenticate or show_version.

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 usage context (official Brazilian tax query) and notes payment (prepaid credits) and lack of platform credentials, but does not explicitly state when to use this tool over alternatives or provide exclusionary conditions. The guidance is mostly implicit.

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