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 effectively describes the tool's behavior by specifying what it returns (list of branches with CNPJ, address, status) and implies it's a read-only operation through 'Lista'. However, it lacks details on potential limitations like rate limits or error handling, which would be beneficial for a tool with no 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 well-structured with clear sections (purpose, usage guidelines, returns), each sentence is necessary and front-loaded with key information. There is no wasted text, and it efficiently communicates the tool's function and context in a compact format.

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 the tool's low complexity (1 parameter, no output schema, no annotations), the description is mostly complete. It covers purpose, usage, and return values adequately. However, without annotations or output schema, it could benefit from more behavioral details like pagination or error cases, but it's sufficient for this simple list operation.

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 input schema has 100% description coverage for its single parameter 'cnpj', so the baseline is 3. The description adds value by clarifying the parameter's purpose in context ('CNPJ base' for listing branches) and implicitly reinforcing it through 'mesmo CNPJ base', but it doesn't provide additional syntax or format details beyond the schema's description.

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 specific action ('Lista todas as filiais') and resource ('de uma empresa'), distinguishing it from siblings like 'buscar_empresa' or 'empresa_completa' by focusing on branch locations rather than company details. It explicitly mentions the scope constraint 'mesmo CNPJ base', which clarifies the tool's unique function.

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 'QUANDO USAR' section provides explicit guidance on when to use this tool: for mapping geographic presence or counting company units. This directly addresses alternative scenarios without naming specific siblings, making it clear when this tool is appropriate versus others like 'buscar_por_cep' or 'empresa_completa'.

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