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 indicates this is a read operation ('Retorna dados') and specifies what data is returned, but doesn't mention potential limitations like rate limits, authentication requirements, or error conditions. The behavioral information is adequate but not comprehensive.

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, front-loading the core purpose and efficiently communicating essential information without unnecessary elaboration.

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 moderate complexity (single parameter, no output schema, no annotations), the description provides good coverage of purpose, usage, and return values. It explains what data is returned in detail, though it doesn't specify format or structure. The description is mostly complete for helping an agent understand when and how to use this tool effectively.

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 schema already documents this parameter well. The description doesn't add any parameter-specific information beyond what's in the schema, but with only one parameter and high schema coverage, a baseline of 3-4 is appropriate. The description focuses appropriately on what the tool does rather than parameter details.

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 with specific verbs ('Retorna dados COMPLETOS') and resources ('empresa'), explicitly listing the three data components returned (cadastro, socios, regime tributario). It effectively distinguishes this tool from sibling tools like 'buscar_empresa' by emphasizing it provides more comprehensive 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 a dedicated 'QUANDO USAR' section with three explicit scenarios for when to use this tool (due diligence, checking socios, verifying tax regime). This provides clear guidance on appropriate contexts, though it doesn't explicitly mention when NOT to use it or name specific alternatives.

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