MCP CNPJ Intelligence

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly describes what the tool returns (a list of partners with specific fields), which is helpful behavioral context. However, it doesn't mention potential limitations like rate limits, authentication requirements, or error conditions. The description doesn't contradict any annotations since none exist.

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 well-structured with clear sections (purpose, usage guidelines, return values) and every sentence adds value. It's appropriately sized for the tool's complexity - not overly verbose but comprehensive enough. The information is front-loaded with the core purpose stated first.

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 single-parameter read-only tool with no output schema, the description provides good contextual completeness. It explains what the tool does, when to use it, and what it returns. The main gap is the lack of output schema, but the description compensates by detailing the return structure. Some additional behavioral context (like limitations or error handling) would make it more complete.

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 100% with the single parameter 'cnpj' already documented in the schema. The description doesn't add any additional parameter information beyond what the schema provides. With high schema coverage, the baseline score of 3 is appropriate since the description doesn't compensate but also doesn't need to given the schema's completeness.

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's purpose: 'Lista o quadro societario completo de uma empresa' (Lists the complete corporate structure of a company). This is a specific verb ('Lista') + resource ('quadro societario') combination that distinguishes it from sibling tools like 'buscar_empresa' or 'empresa_completa' which likely provide broader company information rather than focused ownership data.

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 includes an explicit 'QUANDO USAR' (WHEN TO USE) section with two clear scenarios: when you want to identify owners/partners and when you need their CPF/CNPJ for other searches. This provides specific guidance on when this tool is appropriate versus alternatives, though it doesn't explicitly name sibling tools as alternatives.

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